B&R ACOPOS Error Codes

4007: Lag error stop limit exceeded

What it means: With the position controller active, the lag error (set position minus actual position, PCTRL_LAG_ERROR) went past the limit set in AXLIM_DS_STOP. The error info shows the lag error at the moment of the trip.^[1]

Drive response: Default (STOP_ERR_DECEL_RAMP = ncA_LIMIT): the axis stops on a speed-controlled ramp at the axis limits and the controller switches off.

Likely causes

• Lag error limit AXLIM_DS_STOP set too small
• Speed, acceleration or deceleration set too high for the axis
• Controller tuned too weak, unstable, or feed forward set wrong (for example prediction time 0)
• Drive held at a current, torque, speed, undervoltage or temperature limit
• Higher current demand from friction, jammed mechanics or load shocks
• Encoder fault, motor wiring fault or failed drive hardware

First checks, in this order

1. Read the lag error in the error info and compare it with AXLIM_DS_STOP and with the lag error seen in normal running.
2. Check the move parameters, for example AXLIM_A1_NEG and BASIS_MOVE_V_POS.
3. Trace ICTRL_ISQ_REF: if it sits at sqrt(2) x MOTOR_CURR_MAX, sqrt(2) x ACOPOS_CURR_MAX or a torque limit (LIM_T1_POS, LIM_T1_NEG, LIM_T2_POS, LIM_T2_NEG), the drive is out of current or torque.
4. Check the speed limits SCTRL_LIM_V_POS, SCTRL_LIM_V_NEG and MOTOR_SPEED_MAX.
5. Check the mechanics for binding, then check the encoder (see 4014) and the motor wiring (see 6044 and 6045).
6. Retune the speed and position controllers if the loop is unstable.

7200: DC bus: Overvoltage

What it means: With the controller on, the DC bus voltage UDC_ACT went above the module limit: about 900 VDC on 8Vxxxx.00 models and about 450 VDC on 8Vxxxx.50 models. Most often the braking energy is not being burned off in the braking resistor.^[1]

Drive response: If the voltage falls back under the limit within AXLIM_T_STOP_END, the axis is stopped with short-circuit braking.

Likely causes

• Internal or external braking resistor defective or not connected
• Blown fuse for the external braking resistor
• Defective braking resistor control or bleeder relay inside the drive
• Supply voltage or DC bus voltage too high

First checks, in this order

1. Trace UDC_ACT while braking: it should level off once it passes UDC_BLEEDER_ON. If it keeps rising, the braking circuit is not working.
2. Check the fuse of the external braking resistor.
3. With power off and the DC bus discharged, measure the braking resistance at the plug and compare it with the data sheet, then check the resistor wiring.
4. Measure the mains voltage and the DC bus voltage.
5. If the braking control or relay inside the drive is faulty, replace the ACOPOS module.

7215: Power mains: At least one phase of the power line failed

What it means: The drive has detected that at least one mains phase is missing. Early 8V1022, 8V1045 and 8V1090 units (.00-1, and .00-2 up to Rev. F0) do not have this monitoring.^[1]

Drive response: ACOPOS: same reaction as 7211 (axis stopped). ACOPOSmulti: no reaction.

Likely causes

• Loose contact or a mains phase not connected
• Blown fuse, open contactor, transformer or supply problem
• Drive fed from the DC bus or on single phase with phase monitoring still active

First checks, in this order

1. Check the wiring and measure all phase voltages at the mains connection.
2. Check the contactor, fuses, transformer and supply voltage.
3. If the drive is intentionally fed from the DC bus or single phase, set PHASE_MON_IGNORE = 1 (B&R permits these modes only conditionally).

7211: DC bus: Voltage dip

What it means: The DC bus voltage UDC_ACT fell below POWERFAIL_DETECT_RATIO x UDC_NOMINAL. On 8V drives this error is also raised when a mains phase failure is detected. The error info shows the low voltage limit.^[1]

Drive response: The axis is stopped as for 9000, STAT_UDC_POWERFAIL is set to 2 and the undervoltage limiter is active during the stop.

Likely causes

• Brief mains or phase failure
• High supply impedance or an overloaded or saturating mains transformer
• Loose contact or missing mains phase (see 7215)
• Single-phase operation with too much motor load
• Nominal DC bus voltage detected or initialized wrong

First checks, in this order

1. Record the phase voltages and the DC bus voltage during operation to catch short dips.
2. Check whether the envelope of UDC_ACT drops by more than 10% when the motor is loaded.
3. Check the mains terminals for loose contacts.
4. Compare UDC_NOMINAL with UDC_ACT or with a multimeter reading.

6021: Low level at controller enable input

What it means: The controller enable input does not get enough voltage, either when the controller is switched on or while it is running.^[1]

Drive response: The IGBT power stage switches off, the holding brake engages and the 'controller ready' state is reset.

Likely causes

• Enable switched off by the application program or by manual operation
• Broken wire, wiring error or missing line termination on the enable circuit
• Failed control hardware feeding the enable input
• Problem with the 24 VDC supply of the ACOPOS
• Defective drive

First checks, in this order

1. Measure the voltage on the enable input when the error appears.
2. Follow the enable signal back through its wiring and terminals to its source.
3. Check the ACOPOS 24 VDC supply.
4. Apply the B&R wiring guidelines (shielding and grounding) listed under error 7030.
5. If the input and supply are good, suspect the drive.

4005: Controller cannot be switched on: Drive in error state

What it means: A 'switch on controller' command was given while the drive is in an error state. The real cause is logged as a separate error at the same time, for example 1011 or 6021. The green Ready LED blinks (before firmware V2.130 the red Error LED lit steadily).^[1][2]

Drive response: The power stage is not enabled and the controller stays off.

Likely causes

• Another active drive error, for example enable input low, DC bus voltage out of range or overtemperature

First checks, in this order

1. Look in the Logger for the error entered together with 4005 and fix that one first.
2. Check the Ready LED: blinking green means the drive is not ready.
3. Acknowledge the errors and switch the controller on again.

9300: Current controller: Overcurrent

What it means: The phase current in U or V went above the highest current the module can measure, for example 4.0 A on 8V1010.00-2, 40 A on 8V1045 and 8V1090, and 333 A on 8V1640.^[1]

Drive response: Same as 6019: a synchronous motor is stopped with short-circuit braking.

Likely causes

• Jump in the set current caused by a jump in set position or speed (see 5036) or in the encoder position (see 4014)
• Sudden load change on the motor shaft, such as jammed mechanics or load shocks
• Current controller unstable or set too stiff, or wrong MOTOR_STATOR_INDUCTANCE or MOTOR_ROTOR_INDUCTANCE
• Motor wiring fault, motor defect or drive defect

First checks, in this order

1. Trace ICTRL_ISQ_REF and ICTRL_ISQ_ACT to find the jump that caused the peak.
2. Check the current controller step response for overshoot at the highest current used.
3. Check the motor parameters MOTOR_STATOR_INDUCTANCE and MOTOR_ROTOR_INDUCTANCE.
4. Check the motor cable and motor as described for 6019 and 6045.

6019: ACOPOS: Overcurrent

What it means: At least one of the six inverter transistors, or the braking resistor transistor, reported overcurrent. On 8V1180, 8V1320, 8V1640 and 8V128M it is also raised by the current transformers in U and V.^[1]

Drive response: Synchronous motor: short-circuit braking. Asynchronous motor: power section off and holding brake on. If it happens twice in a row, the power section switches off and the brake engages.

Likely causes

• PE conductor swapped with a motor phase in the motor cable
• Short circuit phase to phase, phase to PE or phase to shield in the motor cable
• Motor winding short, or a short between winding and motor housing
• Failed transistor or braking resistor control inside the drive
• Short circuit in the external braking resistor
• Jump in the set current (see 9300)

First checks, in this order

1. With power off, measure resistance U-V, V-W, W-U, each phase to PE and each phase to the cable shield.
2. Measure the three phase-to-phase impedances at the motor plug and motor terminals; check winding insulation to the housing with a megohmmeter.
3. Check whether the error only appears when UDC_ACT is above UDC_BLEEDER_ON (braking circuit).
4. Disconnect the external braking resistor and test again.

9030: Junction temperature model: Stop limit exceeded

What it means: The calculated IGBT junction temperature TEMP_JUNCTION went above the module limit TEMP_JUNCTION_LIM. In practice the drive is delivering more current than it can sustain.^[1]

Drive response: The axis is stopped as for 9000, with the junction temperature limiter active during the stop.

Likely causes

• Speed and acceleration set too high
• Load torque too high (friction, jammed mechanics, wear, load shocks)
• Unstable controller or wrong commutation offset MOTOR_COMMUT_OFFSET
• Demagnetized or undersized motor
• Supply or DC bus voltage too high (derating)

First checks, in this order

1. Compare the current demand with the motor and drive ratings.
2. Reduce acceleration, increase jolt time, or lower motor peak current and peak torque.
3. Check MOTOR_COMMUT_OFFSET.
4. Check the mechanics for binding.
5. Check MOTOR_TORQ_CONST and MOTOR_VOLT_CONST against the motor data.
6. Check the DC bus voltage against the derating in the user's manual.

9000: Heatsink temperature sensor: Stop limit exceeded

What it means: The heat sink temperature TEMP_HEATSINK went above the stop limit shown in the error info.^[1]

Drive response: 'Controller ready' is reset. On 8V drives with the default STOP_ERR_DECEL_RAMP = ncA_LIMIT, the axis stops at the axis limits and the controller switches off.

Likely causes

• Ambient temperature above 40 °C during operation
• Restricted air flow (wrong mounting direction or covered intake)
• Failed cooling fan
• Faulty heat sink temperature measurement
• Poor thermal contact between IGBT and heat sink (module defect)

First checks, in this order

1. Measure the cooling air temperature right at the intake.
2. Check the mounting direction and keep the intake openings clear.
3. With the controller on, listen for the fan; it gets louder as the heat sink warms up.
4. With the controller off, compare TEMP_HEATSINK with the ambient temperature.
5. Replace the ACOPOS module if the measurement or the thermal path is faulty.

9070: Motor temperature model: Stop limit exceeded

What it means: The drive's calculated motor temperature TEMP_MOTOR_MODELL went above TEMP_MOTOR_MODEL_LIM.^[1]

Drive response: Same as 9000.

Likely causes

• Motor current higher than planned (see 9030)
• Wrong motor data, for example MOTOR_CURR_RATED, MOTOR_CURR_STALL or MOTOR_WIND_CROSS_SECT

First checks, in this order

1. Compare MOTOR_CURR_RATED and MOTOR_CURR_STALL with the motor specification.
2. Check MOTOR_WIND_CROSS_SECT.
3. Check the load and current demand as described for 9030.

9010: Temperature sensor (Motor|Choke|External): Stop limit exceeded

What it means: The temperature measured by the motor temperature sensor (TEMP_MOTOR) went above the stop limit shown in the error info.^[1]

Drive response: Same as 9000.

Likely causes

• Ambient or flange temperature too high for the motor
• Motor air or water cooling not working
• Motor running above its continuous current
• Sensor defect, poorly shielded sensor wires or damaged sensor insulation
• Drive defect

First checks, in this order

1. With the controller off, compare TEMP_MOTOR with the ambient temperature.
2. Compare the average speed and the RMS motor current with the motor's S1 continuous curve.
3. Check the motor cooling.
4. Trace TEMP_MOTOR for spikes that point to noise, and check the sensor wires and shield.

9012: Temperature sensor (Motor|Choke|External): Not connected or destroyed

What it means: The motor temperature sensor reads like an open circuit: above the upper resistance limit for a linear thermistor, or above about 7000 ohm for a PTC switch.^[1]

Drive response: Same as 9000.

Likely causes

• Sensor not connected or a loose contact
• Broken sensor
• Upper resistance limit MOTOR_TEMPSENS_PAR1 or MOTOR_TEMPSENS_PAR2 set too low

First checks, in this order

1. With the controller off, compare TEMP_MOTOR with the ambient temperature.
2. Measure the sensor resistance at the plug with a multimeter.
3. Check the cable and connector pins of the sensor circuit.
4. Check MOTOR_TEMPSENS_PAR1 and MOTOR_TEMPSENS_PAR2.

9050: ACOPOS peak current: Stop limit exceeded

What it means: The drive's peak current load LOAD_PEAK_CURR went above its limit, so the drive is asked for more short-term current than it is rated for.^[1]

Drive response: Same as 9000.

Likely causes

• High current demand from aggressive moves, high load, an unstable controller or a wrong commutation offset (see 9030)

First checks, in this order

1. Trace LOAD_PEAK_CURR over a machine cycle.
2. Reduce acceleration or increase jolt time.
3. Check the mechanics for binding and load shocks.
4. Check the drive sizing against the peak current needed.

9060: ACOPOS continuous current: Stop limit exceeded

What it means: The drive's continuous current load LOAD_CONT_CURR went above its limit, so the drive has been overloaded over time.^[1]

Drive response: Same as 9000.

Likely causes

• High average current from the duty cycle, load or controller problems (see 9030)

First checks, in this order

1. Trace LOAD_CONT_CURR over several cycles.
2. Compare the RMS current of the cycle with the rated drive current.
3. Check the mechanics for friction or binding.
4. Reduce the duty cycle or use a larger drive.

9040: Bleeder temperature model: Stop limit exceeded

What it means: The calculated braking resistor temperature TEMP_BLEEDER went above its limit: TEMP_MAX_BLEEDER_EXT for an external resistor; for the internal resistor 250 °C (8V1010, 8V1016), 350 °C (8V1180, 8V1320) or 400 °C (8V1022, 8V1045, 8V1090, 8V1640, 8V128M).^[1]

Drive response: Same as 9000.

Likely causes

• More regenerative braking energy than the resistor can take
• Linked DC buses where only some drives have the controller switched on, so fewer resistors share the braking power
• Heat sink temperature problem (see 9000)
• DC bus voltage measurement fault in the drive

First checks, in this order

1. Check the braking resistor sizing against the user's manual.
2. With linked DC buses, check how many drives have the controller switched on during braking.
3. Measure the DC bus voltage with a multimeter and compare it with UDC_ACT.

7219: DC bus: Pre-charging: Voltage too low

What it means: At 'switch on controller', with the main relay still open, the filtered DC bus voltage UDC_FILTER is below 0.9 x UDC_NOMINAL.^[1]

Drive response: The controller is not switched on (as 4005).

Likely causes

• Supply voltage or DC bus voltage too low
• UDC_NOMINAL set too high

First checks, in this order

1. Measure the mains voltage and the DC bus voltage.
2. Check the UDC_NOMINAL setting.
3. In the program, wait for the 'controller ready' status before giving 'switch on controller'.

7210: DC bus: Pre-charging: Voltage unstable

What it means: At 'switch on controller' the drive could not find a valid nominal DC bus voltage because UDC_FILTER changed too fast (more than 62.5 V/s rising or 6.25 V/s falling) or briefly left its limits (for example 746 VDC on 8Vxxxx.00 models).^[1]

Drive response: The controller is not switched on (as 4005).

Likely causes

• 'Switch on controller' sent before the DC bus has settled
• Large DC bus fluctuation from a mains disturbance

First checks, in this order

1. In the program, request the 'controller ready' status before 'switch on controller'.
2. Trace UDC_FILTER during power up.
3. Check the mains supply for disturbances.

7212: DC bus: Large voltage dip

What it means: With the controller active, the DC bus voltage fell below 0.65 x UDC_NOMINAL.^[1]

Drive response: The main relay opens, the inverter and chopper power stages switch off, the holding brake engages and 'controller ready' is reset.

Likely causes

• Mains failure
• After a power failure, the energy fed back into the DC bus network is lower than its losses

First checks, in this order

1. Check the mains supply for failures.
2. Check the power balance of the linked DC bus network.

7217: DC bus: Nominal voltage detection: Voltage too high

What it means: At 'switch on controller', with the main relay open, UDC_FILTER is above the braking resistor threshold UDC_BLEEDER_ON or above the module limit (746 VDC on 8Vxxxx.00, 357 VDC on 8Vxxxx.50).^[1]

Drive response: The controller is not switched on (as 7210).

Likely causes

• Supply voltage or DC bus voltage too high

First checks, in this order

1. Measure the mains voltage and the DC bus voltage.
2. Check that the drive variant (.00 or .50) matches the supply voltage.

7218: DC bus: Nominal voltage detection: Voltage too low

What it means: At 'switch on controller', with the main relay open, UDC_FILTER is below 0.9 x UDC_DETECTION, so automatic nominal voltage detection failed.^[1]

Drive response: The controller is not switched on (as 7210).

Likely causes

• Supply voltage or DC bus voltage too low
• UDC_DETECTION set too high

First checks, in this order

1. Measure the mains voltage and the DC bus voltage.
2. Check the UDC_DETECTION setting.

7220: DC bus: Nominal voltage detection: Voltage not allowed

What it means: At 'switch on controller' the DC bus voltage is in a forbidden band: on 8V1180 to 8V128M (internal DC bus supply) between 1.1 x sqrt(2) x 240 and 0.9 x sqrt(2) x 380 VDC (about 373 to 484 VDC), or with PHASE_MON_IGNORE = 1 below 484 VDC (8Vxxxx.00-2) or 293 VDC (8Vxxxx.50-2).^[1]

Drive response: The controller is not switched on (as 7210).

Likely causes

• Mains voltage or DC bus voltage not valid for this drive

First checks, in this order

1. Measure the mains voltage and the DC bus voltage.
2. Check PHASE_MON_IGNORE and the intended supply mode.

7214: DC bus: Pre-charging resistor hot (too many power line fails)

What it means: The DC bus was charged two or more times within 20 seconds on 8V1022, 8V1045 or 8V1090 (.00-1, and .00-2 from Rev. A0 to F0). Switching the mains on more often than every 20 s can damage the charging resistor.^[1]

Drive response: The controller is not switched on (as 7210).

Likely causes

• Mains switched on and off at intervals shorter than 20 s

First checks, in this order

1. Make the machine wait at least 20 s between mains switch-ons.
2. Check the main contactor control logic.

1012: Breakdown of cyclic network communication

What it means: The drive's network card firmware detected a failure in the cyclic POWERLINK communication.^[1]

Drive response: The axis stops as for 9000, all digital and analog outputs are switched off, and the encoder emulation outputs are deactivated.

Likely causes

• Network cable interrupted
• A POWERLINK station failed or is switched off
• Too many stations, hub layers or too much cable length
• Too many stations for the configured POWERLINK cycle time
• Ambient temperature outside the valid range
• Network plug-in card AC114 defective or wrong hardware revision

First checks, in this order

1. Check network cables and connectors from the controller to this drive.
2. Check that every station on the line is powered.
3. Review the topology and the POWERLINK cycle time.
4. Check the PLC diagnostic data points FailedCycleCount, CycleTimeViolationCount and CycleIdleTime.
5. Apply the wiring guidelines under error 7030.

6023: Voltage sag at controller enable input

What it means: The voltage on the controller enable input dipped briefly, at switch on or while the controller was running.^[1]

Drive response: The IGBT power stage switches off, the holding brake engages and 'controller ready' is reset.

Likely causes

• Enable switched off by the program or by manual operation
• Loose or broken connection, wiring error or failed control hardware
• Dips in the ACOPOS 24 VDC supply
• Defective drive

First checks, in this order

1. Check the enable wiring and terminals for loose contacts.
2. Watch the 24 VDC supply for dips when other loads switch.
3. Apply the wiring guidelines under error 7030.

6045: Inverter: Output: No current flow

What it means: When the controller switches on, the drive tests whether current can flow into the motor phases. The measured current was too low. The error info shows the phase.^[1]

Drive response: The IGBT power stage switches off and the holding brake engages.

Likely causes

• A motor phase not connected at the drive output
• Broken motor cable or motor winding
• MOTOR_STATOR_INDUCTANCE or MOTOR_CURR_RATED set too low
• Drive power stage defective

First checks, in this order

1. Check that U, V and W are properly connected at the drive output.
2. Disconnect the phases and measure U-V, V-W and W-U on the cable at the drive end, then at the motor. All three must be equal and finite.
3. Check MOTOR_STATOR_INDUCTANCE and MOTOR_CURR_RATED.
4. If wiring and motor are good, replace the ACOPOS module.

6052: Power stage: High-side: Overcurrent

What it means: At least one of the three high-side transistors (phase U, V or W) in the power stage reported overcurrent.^[1]

Drive response: Same as 6019.

Likely causes

• Motor cable or motor fault (see 6019)
• Failed transistor or gate control in a half-bridge
• Jump in the set current (see 9300)

First checks, in this order

1. Check the motor cable and motor as described for 6019.
2. Unplug the motor cable and try again: if the error still appears, the drive is defective.

6053: Power stage: Low-side: Overcurrent

What it means: At least one of the three low-side transistors (phase U, V or W) in the power stage reported overcurrent.^[1]

Drive response: Same as 6019.

Likely causes

• Motor cable or motor fault (see 6019)
• Failed transistor or gate control in a half-bridge
• Jump in the set current (see 9300)

First checks, in this order

1. Check the motor cable and motor as described for 6019.
2. Unplug the motor cable and try again: if the error still appears, the drive is defective.

6054: Power stage: Overcurrent

What it means: At least one current sensor (phase U, V or W) or the chopper current sensor reported overcurrent.^[1]

Drive response: Same as 6019.

Likely causes

• Motor cable or motor fault (see 6019)
• Drive defect or a current measurement problem
• Braking resistor out of specification or defective
• Jump in the set current (see 9300)

First checks, in this order

1. Check the motor cable and motor as described for 6019.
2. With the power section off, check that the measured phase current reads zero.
3. Check the braking resistor value against the specification.

6036: Motor parameters missing or invalid

What it means: On 'switch on controller' or 'burn motor data', the motor configuration was incomplete. The error info gives the ParID of the first invalid parameter.^[1]

Drive response: The command is not executed.

Likely causes

• A motor parameter not written or written with a wrong value
• MOTOR_TYPE not written as the first motor parameter
• Motor data could not be read from an EnDat encoder memory
• Info 1224 (MOTOR_VENDOR_ID) or 652 (MOTOR_ENCOD_ATTR): B&R EnDat motor with incomplete motor data in Automation Studio 4.0 or later

First checks, in this order

1. Read the ParID in the error info and check that motor parameter in the project.
2. For info 1224 or 652: disable or remove the motor configuration data, upgrade Automation Studio to V4.1.6 or V4.2.3 or later, or add MOTOR_VENDOR_ID = 0 and MOTOR_ENCOD_ATTR = 0.
3. For EnDat motors, check the encoder connection (encoder errors 7xxx).

4008: Positive limit switch reached

What it means: During a move in the positive direction the positive hardware limit switch was reached.^[1]

Drive response: The axis stops at the axis limits; the controller stays on.

Likely causes

• Move without a target position or with a wrong target
• Software limits switched off or set too wide
• Cam automat slave range too large

First checks, in this order

1. Check the move command and target position.
2. Set the software limits inside the hardware limit switches.
3. Check the limit switch, its wiring and its active level (see 4010).

4009: Negative limit switch reached

What it means: During a move in the negative direction the negative hardware limit switch was reached.^[1]

Drive response: The axis stops at the axis limits; the controller stays on.

Likely causes

• Move without a target position or with a wrong target
• Software limits switched off or set too wide

First checks, in this order

1. Check the move command and target position.
2. Set the software limits inside the hardware limit switches.
3. Check the limit switch, its wiring and its active level.

4010: Controller cannot be switched on: Both limit switches are closed

What it means: 'Switch on controller' was given while both the positive and the negative limit switch read closed.^[1]

Drive response: The command is not executed.

Likely causes

• Active input level of the limit switches inverted
• Limit switch held closed mechanically or by hand
• Wire break, wiring error, missing line termination or supply problem

First checks, in this order

1. Check the configured active level of the limit switch inputs.
2. Check both switches mechanically.
3. Check the wiring and the 24 V supply of the switches.
4. For endless or cyclic axes without limit switches, the monitoring can be switched off with LIMIT_SWITCH_IGNORE.

5003: Positive SW limit reached

What it means: During a move, the braking range of the positive software limit was reached and the set speed is zero.^[1]

Drive response: The movement is deactivated; the controller stays on.

Likely causes

• Move in the positive direction without an absolute target position
• Positive software limit set wrong
• Cam automat motion too dynamic for AXLIM_A2_POS

First checks, in this order

1. Check the move command type and target.
2. Check the positive software limit setting.
3. For cam automats, reduce speed or acceleration or check AXLIM_A2_POS.

5004: Negative SW limit reached

What it means: During a move, the braking range of the negative software limit was reached and the set speed is zero.^[1]

Drive response: The movement is deactivated; the controller stays on.

Likely causes

• Move in the negative direction without an absolute target position
• Negative software limit set wrong
• Cam automat motion too dynamic for AXLIM_A2_NEG

First checks, in this order

1. Check the move command type and target.
2. Check the negative software limit setting.
3. For cam automats, reduce speed or acceleration or check AXLIM_A2_NEG.

5001: Target position exceeds positive SW limit

What it means: A move was started to a target beyond the positive software limit, or a positive move was requested while the axis is already outside it.^[1]

Drive response: The new move is not started; an active move is not interrupted.

Likely causes

• Software limit set wrong
• Wrong target position or wrong move command

First checks, in this order

1. Check the target position sent by the program.
2. Check the positive software limit.
3. For endless or cyclic axes, software limit monitoring can be switched off with SGEN_SW_END_IGNORE.

5002: Target position exceeds negative SW limit

What it means: A move was started to a target beyond the negative software limit, or a negative move was requested while the axis is already outside it.^[1]

Drive response: The new move is not started; an active move is not interrupted.

Likely causes

• Software limit set wrong
• Wrong target position or wrong move command

First checks, in this order

1. Check the target position sent by the program.
2. Check the negative software limit.
3. For endless or cyclic axes, software limit monitoring can be switched off with SGEN_SW_END_IGNORE.

5005: Start of movement not possible: Position controller inactive

What it means: A move was started while the position controller is not active.^[1]

Drive response: The move is not started.

Likely causes

• 'Switch on controller' missing, or the program does not wait for the 'controller on' state
• Controller switched off by an earlier drive error
• Controller running in a mode without position control (CONTROLLER_MODE)
• Position control disabled by PCTRL_ENABLE_PARID

First checks, in this order

1. Look for an earlier error that switched the controller off.
2. Check the program sequence: power on, wait for 'controller on', then move.
3. Check CONTROLLER_MODE and PCTRL_ENABLE_PARID.

5006: Start of movement not possible: Axis is not homed

What it means: A move was started while the home position is not valid.^[1]

Drive response: The move is not started.

Likely causes

• Homing command missing, or the program does not wait for 'homing completed'
• Homing aborted by an error

First checks, in this order

1. Run homing and wait for it to complete before moving.
2. Check the Logger for the error that aborted homing.
3. For endless or cyclic axes, this check can be switched off with SGEN_SW_END_IGNORE.

5010: Move in pos. direction not possible: Pos. limit switch is closed

What it means: A positive move was requested while the positive limit switch is closed.^[1]

Drive response: The move is not started.

Likely causes

• Wrong move command or target position
• Limit switch closed by mistake (see 4010)

First checks, in this order

1. Move the axis off the switch in the negative direction.
2. Check the switch, its wiring and its active level.

5011: Move in neg. direction not possible: Neg. limit switch is closed

What it means: A negative move was requested while the negative limit switch is closed.^[1]

Drive response: The move is not started.

Likely causes

• Wrong move command or target position
• Limit switch closed by mistake (see 4010)

First checks, in this order

1. Move the axis off the switch in the positive direction.
2. Check the switch, its wiring and its active level.

4014: Two encoder control: Stop limit of positions difference exceeded

What it means: With two-encoder position control, the difference between the load encoder and the motor encoder positions went above AXLIM_DS_STOP2.^[1]

Drive response: Same as 4007.

Likely causes

• Motor or position encoder configured wrong
• Backlash, elasticity or thermal growth in the mechanics needing a larger AXLIM_DS_STOP2
• Slipping belt or broken coupling
• Encoder, encoder cable, encoder supply or plug-in card fault

First checks, in this order

1. Check the coupling between motor, mechanics and encoder.
2. Check the encoder configuration and the UP/DOWN LEDs on the encoder plug-in card.
3. Watch PCTRL_S_ACT while moving the axis slowly.
4. Check the encoder cable against the wiring guidelines in 7030.

1011: Quickstop input active

What it means: The digital input configured for the quickstop function is active.^[1]

Drive response: 'Drive ready' is reset. By default the axis stops at the axis limits (QUICKSTOP_DECEL_RAMP) and the controller switches off.

Likely causes

• Quickstop triggered by the program or by manual operation
• Wiring fault or failed hardware on the quickstop input

First checks, in this order

1. Find out what drives the quickstop input and why it switched.
2. Check the input wiring and its supply.
3. Check QUICKSTOP_DECEL_RAMP for the stop behavior you expect.

1022: Timeout in life sign monitoring of cyclic data to drive

What it means: With life sign monitoring and the controller active, no cyclic data reached the drive within CYCLIC_TODRV_T_CTRL.^[1]

Drive response: Default: the axis stops at the axis limits and the controller switches off.

Likely causes

• CYCLIC_TODRV_T_CTRL set too short, or monitoring activated before cyclic data is sent
• Counter CYCLIC_TODRV_COUNT not incremented by the program
• Task cycle time exceeded or very high CPU load
• Network disturbance or network load too high

First checks, in this order

1. Check the cyclic task class: duration, tolerance and I/O output delay.
2. Check CYCLIC_TODRV_T_CTRL and when monitoring is switched on.
3. Check the network cabling (wiring guidelines in 7030).

7030: Encoder: Incremental signal amplitude too large

What it means: The sine AB signals of an active encoder are larger than 99% of the measurable range. B&R's page for this error also holds its general encoder and cable wiring guidelines.^[1]

Drive response: With the controller active: short-circuit braking and controller off; 'controller ready', 'homing position valid' and 'commutation valid' are reset.

Likely causes

• Encoder supply missing or faulty, or Sense +5V / Sense COM not connected
• Encoder signal level outside the plug-in card specification
• Encoder cable interrupted or defective
• Read head misaligned, mounting tolerance too large or scale dirty
• Encoder or AC120 / AC121 plug-in card defective

First checks, in this order

1. Check the encoder supply and Sense lines.
2. Compare the encoder data sheet with the plug-in card specification.
3. Check the cable for breaks, loose contacts and correct shielding; shield clamps must be tight.
4. With the encoder cable unplugged at the drive, measure shield to cabinet ground: it must be 0.2 ohm or less.
5. Fit suppressors (varistors, RC elements or diodes) on nearby contactors and relays.

7029: Encoder: Incremental signal amplitude too small

What it means: The sine AB signals are smaller than 17.5% (AC120) or 20% (AC121) of the measurable range.^[1]

Drive response: Same as 7030.

Likely causes

• Encoder supply missing or faulty
• Cable, read head, scale or encoder problems as listed for 7030

First checks, in this order

1. Measure the encoder supply voltage at the encoder.
2. Work through the checks for 7030.

7032: Encoder: Incremental signal amplitude too small (Disturbance, no connection)

What it means: The sine AB signals are below 10% of the measurable range, so the drive does not see the encoder at all.^[1]

Drive response: The internal 'positions synchronous' status is reset; otherwise as 7029.

Likely causes

• Encoder not connected or cable broken
• Encoder supply missing or faulty

First checks, in this order

1. Check that the encoder cable is plugged in at both ends.
2. Measure the encoder supply.
3. Check the cable for continuity.

7031: Encoder: Incremental signal amplitude too large (Disturbance)

What it means: The sine AB signals are above 100% of the measurable range, which usually means interference on the encoder signals.^[1]

Drive response: Same as 7030.

Likely causes

• Electrical noise on the encoder cable
• Causes listed for 7030

First checks, in this order

1. Check shielding and grounding of the encoder cable.
2. Work through the checks for 7030.

7039: Incremental encoder: Cable disturbance track A

What it means: On an incremental encoder, signals A and /A should always be opposite; they overlapped for too long.^[1]

Drive response: Same as 7030.

Likely causes

• Encoder not connected or cable interrupted
• Encoder supply missing or faulty
• Signal level outside the plug-in card specification
• Encoder or AC123 plug-in card defective

First checks, in this order

1. Check the encoder connector and cable, especially the A and /A wires.
2. Measure the encoder supply.
3. Compare the encoder data sheet with the AC123 specification.
4. Apply the wiring guidelines in 7030.

7040: Incremental encoder: Cable disturbance track B

What it means: On an incremental encoder, signals B and /B are not opposite as they should be.^[1]

Drive response: Same as 7030.

Likely causes

• Same causes as 7039, on the B track

First checks, in this order

1. Check the B and /B wires, connector and shield.
2. Work through the checks for 7039.

7041: Incremental encoder: Cable disturbance track R

What it means: On an incremental encoder, the reference pulse signals R and /R are not opposite as they should be.^[1]

Drive response: Same as 7030.

Likely causes

• Same causes as 7039, on the R track
• Encoder without reference pulse while R monitoring is active

First checks, in this order

1. Check the R and /R wires, connector and shield.
2. If the encoder has no reference pulse and none is needed, switch off R monitoring with bit 1 of ENCODx_LINE_CHK_IGNORE.

7043: Encoder: Cable disturbance track D

What it means: On an SSI encoder, the data signals D and /D are not opposite as they should be.^[1]

Drive response: Same as 7030.

Likely causes

• Same causes as 7039, on the SSI data line

First checks, in this order

1. Check the D and /D wires, connector and shield.
2. Work through the checks for 7039.

7044: Encoder: Parity

What it means: The parity bit sent by the encoder does not match the parity the drive calculates from the data bits and PARITY_MODE.^[1]

Drive response: Same as 7030.

Likely causes

• PARITY_MODE does not match the encoder
• Encoder cable interrupted or disturbed
• Encoder or AC123 plug-in card defective

First checks, in this order

1. Compare PARITY_MODE with the encoder data sheet.
2. Check the encoder cable against the wiring guidelines in 7030.

7045: Resolver: Signal disturbance (plausibility check)

What it means: The acceleration calculated from the resolver position is above the allowed maximum ENCODx_A_LIM, so the signal is not plausible.^[1]

Drive response: Same as 7030.

Likely causes

• ENCODx_A_LIM set too tight
• Resolver cable interrupted or disturbed, or resolver not connected
• Resolver outside the AC122 specification, or resolver or AC122 card defective

First checks, in this order

1. Check ENCODx_A_LIM against the real axis acceleration.
2. Check the resolver cable and shield (wiring guidelines in 7030).
3. Compare the resolver data with the AC122 specification.

7046: Resolver: Cable disturbance

What it means: The drive compares the resolver sine and cosine signals as a vector and found too large a deviation. Not supported on 8AC122.60-1 cards.^[1]

Drive response: Same as 7030.

Likely causes

• Same causes as 7045
• Resolver impedance or voltage ratio outside the AC122 specification

First checks, in this order

1. Work through the checks for 7045.
2. Only if the resolver is outside the AC122 specification, the check can be switched off with bit 0 of ENCODx_LINE_CHK_IGNORE. B&R warns this can allow uncontrolled movement on a real resolver fault.

7012: Encoder: Hiperface error bit

What it means: A HIPERFACE encoder set its error bit while a parameter was read or written over the AC121 card, because of a protocol problem or an internal encoder fault.^[1]

Drive response: Error 7013 is entered with the status code.

Likely causes

• Command the encoder could not process
• Internal encoder fault

First checks, in this order

1. Read the status code in the 7013 entry that follows and look it up in the encoder data sheet.
2. Check the encoder cable and supply.

7013: Encoder: Status message

What it means: An active encoder reported a status code, shown in the error info, that describes the fault.^[1]

Drive response: Same as 7030.

Likely causes

• Fault inside the encoder, described by the status code

First checks, in this order

1. Look up the status code in the encoder interface description or the encoder data sheet.

7014: Encoder: CRC error during parameter transfer

What it means: A checksum (CRC) error occurred while data or position was transferred from the encoder.^[1]

Drive response: During encoder initialization the transfer is repeated; while writing a parameter it is aborted.

Likely causes

• Encoder supply dip (check the ACOPOS 24 VDC when the encoder is powered through the plug-in card)
• SSI or serial encoder cable interrupted or disturbed
• Encoder or AC120 / AC121 card defective

First checks, in this order

1. Watch the ACOPOS 24 VDC supply for dips.
2. Check the encoder cable against the wiring guidelines in 7030.
3. Swap the encoder or plug-in card if the error follows it.

7015: Encoder: Timeout error during data transmission

What it means: The encoder did not answer a request from the drive in time.^[1]

Drive response: During encoder initialization the transfer is repeated; while writing a parameter it is aborted.

Likely causes

• Encoder not connected
• Causes listed for 7014

First checks, in this order

1. Check that the encoder cable is plugged in at both ends.
2. Work through the checks for 7014.

7033: Encoder: Incremental position step too large

What it means: The encoder position jumped by more than is physically possible.^[1]

Likely causes

• Encoder speed too high
• Encoder cable interrupted or disturbed
• Encoder configured wrong

First checks, in this order

1. Compare the axis speed with the encoder's maximum speed.
2. Check the encoder cable and shield.
3. Check the encoder configuration.

7036: Encoder: Interface ID invalid (Check slot and Interface EEPROM data)

What it means: The drive cannot use the encoder interface in the slot assigned to this encoder.^[1]

Drive response: Same as 7030.

Likely causes

• No plug-in card in the slot assigned to the encoder
• A card that does not support encoders is in that slot
• Invalid card ID read because of a hardware fault (card, PROM data, bus board, module plug)

First checks, in this order

1. Check which slot the encoder is configured for and what card is fitted there.
2. Reseat the plug-in card and tighten its screws.
3. Swap the card if the error stays.

7038: Encoder: Position value not synchronous with absolute value

What it means: On an absolute encoder, the incremental position on the plug-in card could not be matched to the encoder's serial absolute position.^[1]

Drive response: Same as 7030.

Likely causes

• Serial communication error
• Incremental signal error

First checks, in this order

1. Look in the Logger for the encoder errors entered at the same time and fix those.
2. Check the encoder cable and shield.

7047: Invalid distance of reference marks

What it means: During homing with distance-coded reference marks, the distance between two marks was zero or larger than ENCODx_REF_DCM_DISTANCE.^[1]

Drive response: Homing is aborted (as 5035).

Likely causes

• ENCODx_REF_DCM_DISTANCE does not match the encoder
• Reference signal wire interrupted or disturbed
• Encoder without reference marks, or reference signal outside the card specification
• Dirty scale, or encoder or plug-in card (AC120, AC123, AC130) defective

First checks, in this order

1. Compare ENCODx_REF_DCM_DISTANCE with the encoder data sheet.
2. Check the reference signal wires and shield.
3. Clean the scale and check the read head.

7050: Incremental encoder: Illegal AB signal change

What it means: The quadrature signals of an incremental or SinCos encoder changed in an impossible sequence.^[1]

Drive response: Same as 7030.

Likely causes

• Encoder speed too high
• Encoder cable interrupted or disturbed
• Phase shift between A and B not 90 degrees
• Encoder vibration
• Encoder or module defective

First checks, in this order

1. Compare the axis speed with the encoder's maximum.
2. Check the encoder cable and shield (wiring guidelines in 7030).
3. Check the encoder mounting for vibration.

7051: Encoder: Acceleration too large (Disturbance)

What it means: On a multi-turn encoder, the revolution counter jumped by more than one revolution within 800 µs, which is treated as a disturbance.^[1]

Drive response: Same as 7030.

Likely causes

• Encoder speed too high
• Encoder cable interrupted or disturbed
• Encoder configured wrong or defective

First checks, in this order

1. Check the encoder cable and shield.
2. Check the encoder configuration.
3. Replace the encoder if the error repeats with good wiring.

9001: Heatsink temperature sensor: Switch off limit exceeded

What it means: The heat sink kept heating during the stop that followed 9000 and passed the higher switch-off limit.^[1]

Drive response: Synchronous motor: short-circuit braking; asynchronous motor: eddy-current braking. Current is limited to the motor and drive rated current, then the power stage switches off.

Likely causes

• Same causes as 9000; the axis was stopped too late

First checks, in this order

1. Work through the checks for 9000.
2. Let the drive cool before restarting.

9003: Heatsink temperature sensor: Not connected or destroyed

What it means: The measured heat sink temperature is outside the valid range.^[1]

Drive response: Same as 9000.

Likely causes

• Drive operated outside its specification: ambient too hot or too cold
• Faulty heat sink temperature measurement in the drive

First checks, in this order

1. Check the ambient temperature at the drive.
2. With the controller off, compare TEMP_HEATSINK with the ambient temperature.
3. Replace the drive if the reading is implausible.

9013: Temperature sensor (Motor|Choke|External): Short circuit

What it means: The motor temperature sensor reads like a short circuit: below the lower resistance limit for a linear thermistor, or below MOTOR_TEMPSENS_PAR2 for a PTC switch.^[1]

Drive response: Same as 9000.

Likely causes

• Short circuit in the sensor or its wiring
• Lower resistance limit MOTOR_TEMPSENS_PAR1 or MOTOR_TEMPSENS_PAR2 set too high

First checks, in this order

1. With the controller off, compare TEMP_MOTOR with the ambient temperature.
2. Measure the sensor resistance at the plug with a multimeter.
3. Check MOTOR_TEMPSENS_PAR1 and MOTOR_TEMPSENS_PAR2.

6018: Hardware: Internal power supply failure

What it means: An internal supply voltage of the drive failed. Depending on the hardware it feeds the plug-in cards, fans, current measurement or DC bus relay.^[1]

Drive response: Same as 6021: power stage off, holding brake on.

Likely causes

• Failure or dip of the 24 VDC supply
• Failure or dip of the mains supply
• Drive hardware defect

First checks, in this order

1. Watch the 24 VDC supply for dips.
2. Check the mains supply.
3. Replace the drive if the supplies are stable.

6020: Control supply: Undervoltage

What it means: The control supply voltage dropped below the minimum given in the ACOPOS user's manual.^[1]

Drive response: Same as 6021: power stage off, holding brake on.

Likely causes

• Supply through the DC bus power supply: mains disturbance (broken wire, power failure, dip)
• External 24 V supply out of specification, overloaded, failed or with a broken cable
• Drive hardware defect

First checks, in this order

1. Measure the 24 VDC at the drive terminals under load.
2. Check the supply rating against the total load.
3. Check the mains if the drive takes its control supply from the DC bus.

6044: Phasing: Rotational direction or position not valid

What it means: Phasing in stepper mode (PHASING_MODE = 1) gave an invalid result. The error info shows the calculated number of pole pairs.^[1]

Drive response: Phasing is aborted.

Likely causes

• Negative pole pair count: two motor phases swapped
• Count between -0.5 and 0.5: wrong encoder scaling SCALE_ENCODx_INCR, motor phase not connected, load torque, or holding brake not opening
• Encoder position or speed error (see 4014)

First checks, in this order

1. For a negative count, swap two motor phases or set MOTOR_CURR_ROT_DIR = ncINVERSE.
2. Watch the motor during phasing: it should turn through 10 pole pairs.
3. Check SCALE_ENCODx_INCR, the brake release and the motor connection.

6046: Phasing: No rotor movement

What it means: During phasing in dither mode (PHASING_MODE = 2), the measured speed SCTRL_SPEED_ACT stayed too low.^[1]

Drive response: Phasing is aborted.

Likely causes

• Rotor blocked by the holding brake, an external load or very high inertia
• Phasing current PHASING_CURR too low to make torque
• Encoder error (see 4014)
• Two motor phases disconnected or a loose terminal

First checks, in this order

1. Trace SCTRL_SPEED_ACT during phasing.
2. Make sure the brake opens and the axis is free to move.
3. Check PHASING_CURR and the motor connection (see 6045).

6029: Holding brake: Control signal on and output status off

What it means: The brake output was switched on, but the brake did not get enough current or voltage within BRAKE_CTRL_MON_FILTER.^[1]

Drive response: With the controller off: none. Otherwise as 9000.

Likely causes

• Brake wiring fault or broken wire
• Brake or external relay outside the drive specification or defective
• Brake output voltage too low
• Brake control inside the drive defective

First checks, in this order

1. Check the brake wiring as shown in the user's manual for this module.
2. Measure the brake coil resistance and the voltage at the brake while it should be released.
3. Check the external brake relay if used.

6056: Holding brake: Low current

What it means: The brake output is on, but too little current flows to the holding brake.^[1]

Drive response: Same as 6029.

Likely causes

• Required jumpers S1-S2 and S3-S4 not fitted, or other wiring error
• Broken brake wire
• Brake or external relay outside the drive specification (for example coil resistance too high)
• External relay, brake or drive brake control defective

First checks, in this order

1. Check the brake wiring and jumpers as specified in the user's manual.
2. Measure the brake coil resistance.
3. If the brake or relay is legitimately outside the specification, monitoring can be switched off with bit 2 of BRAKE_MODE.

6048: Motor holding brake movement monitor: Position error too large

What it means: With the holding brake closed, the motor encoder moved more than BRAKE_TEST_POS_LIM. The brake is slipping and will wear faster.^[1]

Drive response: During a brake torque test the test is aborted; otherwise none.

Likely causes

• Brake closing delay set too short
• Motor encoder configured wrong
• BRAKE_TEST_POS_LIM too small for normal play
• Load torque too high or axis not halted under position control
• Worn or defective brake

First checks, in this order

1. Check the brake closing delay setting.
2. Check BRAKE_TEST_POS_LIM against the mechanical play.
3. Run the brake torque test and replace the brake if it slips.
4. If the brake test is not used, standstill monitoring can be switched off with bit 3 of BRAKE_MODE.

32189: Timeout for cyclic data from drive - Indications invalid (network error ?)

What it means: Raised on the PLC side: after network communication was running, the ACOPOS driver received no cyclic data from this drive for a set time.^[1]

Drive response: The ACOPOS driver sets network communication for this drive to not active.

Likely causes

• POWERLINK cycle time set too low
• Network overload, malfunction or interruption
• Drive failed or lost power

First checks, in this order

1. Check the drive's LEDs and 24 VDC supply.
2. Check the network cables and connectors.
3. Check the POWERLINK cycle time and look for 1012 on the drive.

32204: Timeout while reading par. via acyclic channel (is the drive in the network ?)

What it means: Raised on the PLC side: the ACOPOS driver sent an acyclic read request but got no answer from the drive in time.^[1]

Drive response: The acyclic POWERLINK read channel is reset.

Likely causes

• Network overload, malfunction or interruption
• Drive failed or not on the network

First checks, in this order

1. Check that the drive is powered and its network LEDs are normal.
2. Check the network cables and connectors.
3. Look for 1012 on the drive.

32010: Drive not responding to Read Request (is the drive in the network ?)

What it means: Raised on the PLC side: a read request placed in the cyclic POWERLINK frame got no response from the drive in time. The error info shows the timeout.^[1]

Drive response: The read channel interface is reset.

Likely causes

• Network overload, malfunction or interruption
• Drive failed or not on the network

First checks, in this order

1. Check that the drive is powered and booted.
2. Check the network cables and connectors.
3. Look for 1012 on the drive.

41001: Heatsink temperature sensor: Warning limit exceeded

What it means: The heat sink temperature TEMP_HEATSINK passed the warning limit of 0.95 x 103 °C (about 98 °C). The drive keeps running.^[1]

Drive response: None.

Likely causes

• Same causes as 9000: hot ambient, poor air flow, failed fan

First checks, in this order

1. Work through the checks for 9000 before the drive reaches the stop limit.

41011: Temperature sensor (Motor|Choke|External): Warning limit exceeded

What it means: The motor sensor temperature TEMP_MOTOR passed the warning limit: 0.95 x 110 °C when MOTOR_COMPATIBILITY = 513, otherwise 0.95 x MOTOR_WIND_TEMP_MAX. The drive keeps running.^[1]

Drive response: None.

Likely causes

• Same causes as 9010: hot ambient, cooling problem, motor above its continuous current, sensor fault

First checks, in this order

1. Work through the checks for 9010 before the motor reaches the stop limit.

41031: Junction temperature model: Warning limit exceeded

What it means: The calculated IGBT junction temperature passed 95% of its allowed maximum. The drive keeps running.^[1]

Drive response: None.

Likely causes

• Same causes as 9030: high current demand

First checks, in this order

1. Work through the checks for 9030.

41041: Bleeder temperature model: Warning limit exceeded

What it means: The calculated braking resistor temperature passed 95% of its allowed maximum. The drive keeps running.^[1]

Drive response: None.

Likely causes

• Same causes as 9040: too much braking energy for the resistor

First checks, in this order

1. Work through the checks for 9040.

41051: ACOPOS peak current: Warning limit exceeded

What it means: The drive's peak current load LOAD_PEAK_CURR passed 95%. The drive keeps running.^[1]

Drive response: None.

Likely causes

• Same causes as 9050

First checks, in this order

1. Work through the checks for 9050.

41061: ACOPOS continuous current: Warning limit exceeded

What it means: The drive's continuous current load LOAD_CONT_CURR passed 95%. The drive keeps running.^[1]

Drive response: None.

Likely causes

• Same causes as 9060

First checks, in this order

1. Work through the checks for 9060.

41070: Motor temperature model: Warning limit exceeded

What it means: The calculated motor temperature passed 95% of the way from rated ambient (MOTOR_AMB_TEMP_RATED) to its limit. The drive keeps running.^[1]

Drive response: None.

Likely causes

• Same causes as 9070

First checks, in this order

1. Work through the checks for 9070.

38008: Bleeder: No current flow

What it means: At controller switch on, an 8V drive pulses the braking chopper for 20 ms and expects the DC bus to drop by more than 2%. It dropped less, so the braking resistor circuit looks open.^[1]

Drive response: None.

Likely causes

• Blown fuse or defective chopper in the drive
• External braking resistor wires loose at RB+ and RB-
• Broken braking resistor or resistor cable

First checks, in this order

1. Check that the braking resistor wires are tight at RB+ and RB-.
2. With power off and the DC bus discharged, remove the wires and measure RB+ to RB- on the cable, then at the resistor. It must be finite and match the resistor data.
3. Replace the fuse, or the drive if the chopper is defective.
4. The warning can be switched off with bit 6 (0x40) of MOTOR_TEST_MODE.

39001: Encoder: Position correction active

What it means: On a SinCos or serial encoder (EnDat, HIPERFACE, SSI), the incremental position and the serial absolute position differed too much over several comparisons. Entered once.^[1]

Drive response: The incremental position is corrected to the absolute position.

Likely causes

• AB signal cable interrupted or disturbed
• Problem with the serial absolute position
• Encoder or AC120 / AC121 card defective

First checks, in this order

1. Check the encoder cable and shield (wiring guidelines in 7030).
2. Look for other encoder warnings or errors logged at the same time.

39010: EnDat encoder: Alarm bit - Battery change required

What it means: The battery of a battery-buffered EnDat encoder is low. Movements while the encoder is unpowered are not counted, so the multi-turn position is invalid.^[1]

Drive response: None.

Likely causes

• Encoder battery worn out
• Encoder supply missing or faulty

First checks, in this order

1. Change the encoder battery.
2. Acknowledge by setting PARID_ENCOD_CMD = 1.
3. Re-establish the multi-turn position (home the axis) afterwards.