Hitachi SJ700 Error Codes

E01: Overcurrent protection (during constant-speed operation)

What it means: Output current reached the trip level (about 220% of the drive's rated output current) while the motor ran at steady speed, so the drive cut its output. The remote operator shows OC.Drive.^[1][4][5][6]

Also on: SJ200 (NB650XA), X200 (NT301XC) and WJ200 (NT325DX): E01 Over-current event while at constant speed.

Likely causes

• Sharp load change or a jam on the driven machine
• Short circuit in the output cables or motor
• Ground fault in the output cables or motor

First checks, in this order

1. Look for a jam, binding or a sudden load swing on the machine.
2. With power off and the Charge lamp out, check the output cables and motor for shorts and ground faults.
3. Read d081 for the output current and frequency at the moment of the trip.
4. If load peaks are normal for the process, use overload restriction (b021, b022) or overcurrent suppression (b027 = 01).

E02: Overcurrent protection (during deceleration)

What it means: Output current reached the trip level while the drive was slowing the motor down. The remote operator shows OC.Decel.^[1][4][5][6]

Also on: SJ200 (NB650XA), X200 (NT301XC) and WJ200 (NT325DX): E02 Over-current event during deceleration.

Likely causes

• Deceleration time too short for the load inertia
• Short circuit or ground fault on the output side

First checks, in this order

1. Increase the deceleration time (F003).
2. Check the output cables and motor for shorts and ground faults.
3. Read d081 to confirm the trip happened while decelerating (status digit 2).

E03: Overcurrent protection (during acceleration)

What it means: Output current reached the trip level while the drive was speeding the motor up. The remote operator shows OC.Accel.^[1][4][5][6]

Also on: SJ200 (NB650XA), X200 (NT301XC) and WJ200 (NT325DX): E03 Over-current event during acceleration.

Likely causes

• Acceleration time too short
• Motor or machine locked or binding
• Torque boost set too high

First checks, in this order

1. Increase the acceleration time (F002).
2. Check the motor and machine for a locked rotor, and the wiring for shorts.
3. Reduce the manual torque boost (A042) if it was raised.
4. Consider overload restriction (b021, b022) to hold the ramp while current is high.

E04: Overcurrent protection (others)

What it means: Output current reached the trip level in a state other than acceleration, deceleration or constant speed, for example during DC braking. The remote operator shows Over.C.^[1][4][5][6]

Also on: SJ200 (NB650XA), X200 (NT301XC) and WJ200 (NT325DX): E04 Over-current event during other conditions.

Likely causes

• DC braking force set too high
• Faulty current detector (CT)

First checks, in this order

1. Reduce the DC braking force (A054) and review the DC braking settings (A051 and related).
2. If the trip repeats with no braking or load cause, have the current detector (CT) checked and repaired.

E001: Overcurrent error

What it means: Output current went above the overcurrent level set in bb160, so the drive turned its output off. The SJ-P1 uses one code for every operating state; the trip detail screen shows the state.^[2][3]

Also on: SJ700 (NT204DX): E01 to E04, split by operating state.

Likely causes

• Acceleration or deceleration time too short, or high load inertia or friction
• Ground fault, short circuit or open phase on the output
• Motor locked or a steep load change
• Motor hunting from wrong motor data
• Failed output element or current detector (trip right after power-on)

First checks, in this order

1. Lengthen the acceleration time (FA-10 or AC120) or deceleration time (FA-12 or AC122).
2. Adjust torque boost (Hb141) or the control mode (AA121).
3. Enable overcurrent suppression (bA120) and overload restriction (bA122).
4. Check motor data (Hb102, Hb103) and run auto-tuning (HA-01).
5. Power off, disconnect the motor leads and power the drive alone: if E001 still appears, the drive needs repair.
6. Use the overcurrent retry count (bb-22) only after the cause is known.

E07: Overvoltage protection

What it means: The DC voltage across P and N went above about 400 V DC (200 V class) or 800 V DC (400 V class), usually from energy the motor sends back while braking. The remote operator shows Over.V.^[1][4][5][6]

Also on: SJ200 (NB650XA), X200 (NT301XC) and WJ200 (NT325DX): E07 Over-voltage protection.

Likely causes

• Deceleration time too short
• Load driving the motor (overhauling load, high inertia)
• Ground fault on the output
• High supply voltage

First checks, in this order

1. Increase the deceleration time (F003).
2. Enable overvoltage suppression (b130) and check its level (b131).
3. If braking energy is high, fit a braking resistor or braking unit and check the braking use ratio (b090).
4. Check the output cables and motor for a ground fault.
5. Check the supply voltage.

E007: Overvoltage error

What it means: P-N voltage went above about 410 V DC (200 V class) or 820 V DC (400 V class), so the drive turned its output off.^[2][3]

Also on: SJ700 (NT204DX): E07 Overvoltage protection.

Likely causes

• Deceleration time too short or high load inertia
• Load turning the motor faster than the drive output (fan, crane)
• Supply voltage high or fluctuating (trip while stopped)
• Two drives on one shaft fighting each other in drooping control

First checks, in this order

1. Lengthen the deceleration time (FA-12 or AC122).
2. Enable overvoltage suppression (bA140, bA146).
3. Add a braking resistor, braking unit or regenerative converter (bA-60 to bA-63).
4. If it trips while stopped, check the supply and consider an AC reactor.
5. On two drives sharing a shaft, set one of them to P control.
6. Use the overvoltage retry count (bb-23) only after the cause is known.

E05: Overload protection

What it means: The electronic thermal function calculated a motor overload from the output current and tripped the drive. The remote operator shows Over.L. Reset is not accepted for about 10 seconds.^[1][4][5][6]

Also on: SJ200 (NB650XA), X200 (NT301XC) and WJ200 (NT325DX): E05 Overload protection.

Likely causes

• Motor load too high
• Electronic thermal level set too low for the motor
• Long running at 5 Hz or less, or a high-inertia start

First checks, in this order

1. Reduce the load or check the machine for drag.
2. Check the electronic thermal level (b012) and characteristic (b013) against the motor nameplate.
3. If a high-inertia start stalls at low speed, raise the torque boost.
4. Wait about 10 seconds before resetting.

E005: Motor overload error

What it means: The built-in electronic thermal function detected a motor overload and turned the output off. Reset is not accepted for 10 seconds.^[2][3]

Also on: SJ700 (NT204DX): E05 Overload protection.

Likely causes

• Heavy load for a long time
• Motor thermal level (bC110) set wrong
• Acceleration or deceleration too fast, or high inertia
• Overcurrent or overvoltage suppression raising the current
• Dirty fan, clogged duct or aging parts after long use

First checks, in this order

1. Review the load and the duty cycle.
2. Check the motor thermal level (bC110) and the thermal decrease setting (bC112).
3. Lengthen the acceleration (FA-10 or AC120) or deceleration time (FA-12 or AC122).
4. Use overload restriction (bA122) and run auto-tuning (HA-01) if the motor sounds abnormal.
5. Wait 10 seconds before resetting.

E039: Controller overload error

What it means: The electronic thermal function for the inverter itself detected a drive (controller) overload and turned the output off. Reset is not accepted for 10 seconds.^[2][3]

Likely causes

• Heavy load running for a long time
• Fast acceleration or deceleration with high inertia
• Overcurrent or overvoltage suppression raising the current

First checks, in this order

1. Reduce the load or correct the operating conditions.
2. Lengthen the acceleration (FA-10 or AC120) or deceleration time (FA-12 or AC122).
3. Use overload restriction (bA122).
4. Wait 10 seconds before resetting.

E09: Undervoltage

What it means: The P-N DC voltage fell below about 175 V DC (200 V class) or 345 V DC (400 V class), too low for the control circuit, so the drive shut off its output. The remote operator shows Under.V.^[1][4][5][6]

Also on: SJ200 (NB650XA), X200 (NT301XC) and WJ200 (NT325DX): E09 Under-voltage error.

Likely causes

• Supply voltage dropped
• Supply capacity too small
• Damaged thyristor in the drive's input circuit
• Poor contacts in the breaker or contactor

First checks, in this order

1. Measure the supply voltage at the drive input, ideally while running.
2. Check the supply capacity and the breaker and contactor contacts.
3. If dips are expected, set restart after power failure (b001, b002, b004).
4. If the supply is good, have the drive's thyristor checked.

E009: Undervoltage error

What it means: The P-N voltage fell below about 160 V DC (200 V class) or 320 V DC (400 V class), so the drive turned its output off to protect its circuits.^[2][3]

Also on: SJ700 (NT204DX): E09 Undervoltage.

Likely causes

• Power failure or supply dip
• Supply capacity too small at start
• Supply voltage does not match the drive's voltage class
• Aged capacitors or a circuit fault after long use

First checks, in this order

1. Check the supply voltage and capacity.
2. Use undervoltage retries (bb-21) if short dips are normal on site.
3. Use bb-27 to stop undervoltage trips while the drive is stopped.
4. If it happens often on an old drive, have it repaired.

E14: Ground-fault protection

What it means: At power-on the drive checks for a ground fault between its output and the motor, and trips if it finds one. The check does not work while the motor still carries residual voltage. The remote operator shows GND.Flt. Reset only by a power cycle.^[1][4][5][6]

Also on: SJ200 (NB650XA), X200 (NT301XC) and WJ200 (NT325DX): E14 Ground fault.

Likely causes

• Ground fault in the motor cable or motor
• Degraded motor insulation
• Fault inside the drive's main circuit

First checks, in this order

1. Power off and wait for the Charge lamp to go out.
2. Disconnect the output cables and check the motor and cables for a ground fault.
3. Power the drive with the output cables removed to see if the drive itself trips.
4. Check the main circuit as described in the maintenance chapter, or send the drive for repair.

E014: Ground fault error

What it means: At power-on the drive detected a ground fault between its output and the motor. It is a serious fault: the MJA output turns on and RS does not clear it.^[2][3]

Also on: SJ700 (NT204DX): E14 Ground-fault protection.

Likely causes

• Ground fault in the motor wiring or motor
• Motor insulation deterioration

First checks, in this order

1. Turn the power off, remove the motor wires and check the motor and wires.
2. Do not switch the power back on while a ground fault is present.
3. Ground fault detection is set in bb-64 (00 off, 01 on).
4. Cycle the power to clear the trip once the fault is fixed.

E30: IGBT error

What it means: The drive protected its power transistors (IGBTs) after an instantaneous overcurrent, an abnormal IGBT temperature or a drop in IGBT drive power. The drive does not retry after this trip. The remote operator shows IGBT. On models 004 to 110L/H, only a power cycle clears it.^[1][5][6]

Also on: X200 (NT301XC) and WJ200 (NT325DX): E30 is named Driver error, an internal fault in the protection circuit between the CPU and the driver, with electrical noise as a possible cause.

Likely causes

• Short circuit on the output
• Ground fault in the output cables or motor
• Damaged IGBT
• Clogged heat sink

First checks, in this order

1. Check the output cables for a short circuit.
2. Check the output cables and motor for a ground fault.
3. Clean the heat sink.
4. If the wiring is good, have the IGBT module checked.

E030: IGBT error

What it means: An instantaneous overcurrent or a main element failure made the drive turn its output off to protect the main element. The drive may show an overcurrent error instead.^[2][3]

Also on: SJ700 (NT204DX): E30 IGBT error.

Likely causes

• Ground fault or short circuit on the output
• Motor locked
• Broken output element

First checks, in this order

1. Power off and check the motor wires and the motor.
2. If E030 still appears with the motor wires removed, the drive needs repair.
3. Remove the cause of a locked motor.

E21: Temperature error

What it means: The main circuit got too hot, for example from a high ambient temperature, so the drive shut off its output. The remote operator shows OH.fin.^[1][4][5][6]

Also on: SJ200 (NB650XA), X200 (NT301XC) and WJ200 (NT325DX): E21 Inverter thermal trip.

Likely causes

• High ambient temperature
• Drive not mounted vertically or without enough clearance
• Clogged heat sink or weak cooling fan

First checks, in this order

1. Check that the drive is mounted vertically with the required clearance.
2. Lower the cabinet or room temperature.
3. Clean the heat sink and check the cooling fan.
4. Consider a lower carrier frequency (b083).

E021: Temperature error

What it means: The inside of the drive got too hot, so the drive turned its output off.^[2][3]

Also on: SJ700 (NT204DX): E21 Temperature error.

Likely causes

• Clogged heat sink fins
• High ambient temperature or poor cooling around the drive
• Installation not as specified
• High carrier frequency
• Broken temperature detector circuit (trip while stopped)

First checks, in this order

1. Clean the heat sink fins.
2. Improve cooling and ventilation around the drive.
3. Install the drive as the manual specifies.
4. Lower the carrier frequency (bb101).
5. If it trips again while stopped after a reset, have the drive repaired.

E20: Temperature error due to low cooling-fan speed

What it means: A temperature error occurred while the drive also detected a slow cooling fan. The remote operator shows OH.stFAN. The drive also sets the major failure (MJA) signal.^[1]

Likely causes

• Worn or failing cooling fan
• Clogged heat sink

First checks, in this order

1. Replace the cooling fan.
2. Clean the heat sink.

E020: Cooling fan rotation speed reduction temperature error

What it means: The drive overheated because its cooling fan slowed down. It is a serious fault (MJA output on), but it can be reset after the drive temperature drops.^[2][3]

Also on: SJ700 (NT204DX): E20 Temperature error due to low cooling-fan speed.

Likely causes

• Cooling fan near or at the end of its life
• Fan stopped
• Foreign object stuck in the fan

First checks, in this order

1. Remove any foreign object from the fan.
2. Replace the cooling fan if it is slow or stopped.
3. Let the drive cool down, then reset.

E12: External trip

What it means: An external device signaled a fault on the input set to EXT (function 12), so the drive shut off its output. The remote operator shows EXTERNAL.^[1][4][5][6]

Also on: SJ200 (NB650XA), X200 (NT301XC) and WJ200 (NT325DX): E12 External trip.

Likely causes

• Fault in the external equipment wired to the EXT input
• Wiring fault or wrong contact logic on that input

First checks, in this order

1. Find and clear the fault in the external equipment.
2. Check which input among C001 to C008 is set to 12 (EXT) and its wiring.
3. Check the input's normally open or normally closed setting.

E012: External trip error

What it means: The input set to 033 (EXT) turned on, or an external trip came by communication, so the drive turned its output off.^[2][3]

Also on: SJ700 (NT204DX): E12 External trip.

Likely causes

• Fault in an external device
• Input logic reversed (a/b contact)
• Wrong wiring
• External trip command sent by communication or an EzSQ program

First checks, in this order

1. Check the state of the external devices.
2. Check the input terminal monitor (dA-51) and the terminal set to 033 (EXT).
3. Check the a/b contact setting of that input.
4. Check for trip commands from the network or an EzSQ program.

E13: USP error

What it means: With unattended start protection on (an input set to 13, USP), the drive was powered up while a run command was still present. The remote operator shows USP.^[1][4][5][6]

Also on: SJ200 (NB650XA), X200 (NT301XC) and WJ200 (NT325DX): E13 USP.

Likely causes

• Run command left on when power came back
• Control sequence gives the run command before the drive is powered

First checks, in this order

1. Remove the run command, then reset or power up again.
2. Change the control sequence so the run command comes after power-up.

E013: USP error

What it means: With USP enabled (input 034), a run command was present when power came on. The drive checks for a run command for 1 second after power-up; keypad and communication run commands also count.^[2][3]

Also on: SJ700 (NT204DX): E13 USP error.

Likely causes

• Run command entered too early after power-up
• Run command not released before power-up
• Run from keypad or network while USP is on

First checks, in this order

1. Release the run command when power is switched on.
2. Wait 2 seconds or more after power-up before giving the run command.
3. Check the input terminal monitor (dA-51).

E08: EEPROM error

What it means: The internal EEPROM had an error from electrical noise or high temperature. The remote operator shows EEPROM. RS and STOP/RESET do not clear it: switch the power off and on. If E08 appears again at power-up, the memory may have failed or parameters were not saved.^[1][4][5][6]

Also on: SJ200 (NB650XA), X200 (NT301XC) and WJ200 (NT325DX): E08 EEPROM error. The SJ200 and X200 manuals add that switching power off while the RS input is on can cause E08 at the next power-up.

Likely causes

• Electrical noise near the drive
• High drive temperature from a clogged heat sink or failing fan

First checks, in this order

1. Remove or shield noise sources near the drive.
2. Clean the heat sink and replace the cooling fan if needed.
3. Cycle the power. If E08 returns, initialize the drive (b084) and enter the parameters again.
4. Check all parameter values after the error.

E008: Memory error

What it means: The built-in memory had a problem, so the drive turned its output off (a CPU error may show instead). Cycle the power and then check the parameters.^[2][3]

Also on: SJ700 (NT204DX): E08 EEPROM error.

Likely causes

• Electrical noise
• Power switched off while the drive was writing to memory

First checks, in this order

1. Take noise countermeasures, such as a shielding plate.
2. Cycle the power and check the parameters.
3. Restore the parameters from a keypad backup if one exists, otherwise initialize the drive.
4. If initialization does not help, send the drive for repair.

E16: Instantaneous power failure protection

What it means: A power interruption of 15 ms or more made the drive shut off its output. A long outage counts as a normal power-off. With a restart mode set and a run command present, the drive restarts when power returns. The remote operator shows Inst.P-F.^[1]

Likely causes

• Supply voltage dip or short outage
• Poor contacts in the breaker or magnetic contactor

First checks, in this order

1. Check the supply for dips and outages.
2. Check and replace worn breakers or contactors.
3. To ride through short outages, set the restart mode (b001), allowed outage time (b002), restart wait (b003) and trip selection (b004).

E016: Instantaneous power failure error

What it means: A drop of the main power on R, S or T made the drive turn its output off. A drop of only the control supply on R0 and T0 does not cause this error when the J51 connector is removed and R0, T0 are fed separately.^[2][3]

Also on: SJ700 (NT204DX): E16 Instantaneous power failure protection.

Likely causes

• Supply voltage dropped or a short power failure
• Supply capacity too small
• Contact fault in a breaker, contactor or earth-leakage breaker

First checks, in this order

1. Check the supply voltage and capacity.
2. Check breakers and contactors for contact faults.
3. Use retries after instantaneous power failure (bb-20) so the drive restarts when power returns.

E24: Phase loss input protection

What it means: With phase loss protection on (b006 = 01), the drive found a missing input phase for about 1 second and tripped. The remote operator shows PH.fail.^[1]

Likely causes

• Missing input phase or blown supply fuse
• Poor contacts in the breaker or contactor

First checks, in this order

1. Check the power supply input wiring and fuses.
2. Check and replace worn breakers or contactors.
3. Check that b006 is set as intended.

E024: Input open-phase error

What it means: With input phase loss detection on (bb-65 = 01), the drive found a missing phase on the input line.^[2][3]

Also on: SJ700 (NT204DX): E24 Phase loss input protection.

Likely causes

• Loose or disconnected input line or breaker
• Single-phase supply used on a three-phase input

First checks, in this order

1. Power off and check the input lines, terminal screws and breaker.
2. Use a three-phase connection.
3. Check the bb-65 setting.

E034: Output open-phase error

What it means: With output phase loss detection on (bb-66 = 01), the drive found a loose or broken output line or a break inside the motor. Detection works between 5 Hz and 100 Hz.^[2][3]

Likely causes

• Loose or disconnected output line or motor connection
• Motor insulation breakdown or a break inside the motor
• Single-phase output wiring

First checks, in this order

1. Power off and check the output lines and motor terminals; tighten loose screws.
2. Check the motor windings.
3. Use all three output phases.
4. Check the bb-66 setting.

E06: Braking resistor overload protection

What it means: The braking circuit (BRD) use rate went above the limit set in b090, so the drive shut off its output. The remote operator shows OL.BRD.^[1][4][6]

Also on: SJ200 (NB650XA) and WJ200 (NT325DX): E06 Braking resistor overload.

Likely causes

• Deceleration too fast
• Operating cycle too short
• BRD use rate (b090) set too low

First checks, in this order

1. Increase the deceleration time (F003).
2. Lengthen the operating cycle.
3. Set b090 to a suitable level within the resistor's allowed capacity.

E006: Braking resistor overload error

What it means: The braking circuit (BRD) use rate went above the rate set in bA-60, so the drive turned its output off.^[2][3]

Also on: SJ700 (NT204DX): E06 Braking resistor overload protection.

Likely causes

• Deceleration time too short or high inertia
• Stops repeated too often
• Continuous regeneration, for example a crane lowering or a fan turned by wind
• Braking resistor too small

First checks, in this order

1. Lengthen the deceleration time (FA-12 or AC122).
2. Reduce how often the machine stops.
3. Review the braking resistor size and the bA-60 setting.

E15: Input overvoltage protection

What it means: While stopped, the input voltage stayed high for 100 seconds: main circuit DC voltage above about 390 V DC (200 V class) or 780 V DC (400 V class). The remote operator shows OV.SRC.^[1][4][5][6]

Also on: SJ200 (NB650XA), X200 (NT301XC) and WJ200 (NT325DX): E15 Input over-voltage.

Likely causes

• Supply voltage too high
• Supply voltage swings

First checks, in this order

1. Measure the input voltage while the drive is stopped.
2. Lower the supply voltage or reduce its swings.
3. Fit an AC reactor between the supply and the drive input.

E015: Incoming overvoltage error

What it means: With bb-61 set to 01 (error), the P-N voltage stayed above the level in bb-62 for 100 seconds while the output was stopped.^[2][3]

Also on: SJ700 (NT204DX): E15 Input overvoltage protection.

Likely causes

• High incoming supply voltage
• Unstable supply, for example after equipment changes on site

First checks, in this order

1. Review the power supply.
2. Check the DC bus voltage monitor (dA-40).
3. Check the bb-61 and bb-62 settings.

E35: Thermistor error

What it means: The motor thermistor on the TH terminal showed the motor is too hot, so the drive shut off its output. The remote operator shows TH.^[1][4][5][6]

Also on: SJ200 (NB650XA), X200 (NT301XC) and WJ200 (NT325DX): E35 Thermistor.

Likely causes

• Motor overheating
• Damaged thermistor in the motor
• Noise on the thermistor wiring

First checks, in this order

1. Check the motor temperature, load and cooling.
2. Check the thermistor.
3. Route the thermistor wiring away from power wiring.
4. Check the thermistor type (b098) and level (b099).

E035: Thermistor error

What it means: With the thermistor function on, the external motor thermistor reached an abnormal temperature level, so the drive turned its output off.^[2][3]

Also on: SJ700 (NT204DX): E35 Thermistor error.

Likely causes

• Motor not cooled enough
• Heavy load for a long time
• Wrong thermistor setting
• Broken thermistor (motor not hot)
• Noise on the thermistor wiring

First checks, in this order

1. Improve motor cooling and review the load.
2. Check the thermistor settings (Cb-40).
3. Check the thermistor itself.
4. Separate the thermistor wiring from power wiring.
5. Consider overload restriction (bA122).

E41: Modbus communication error

What it means: Modbus-RTU communication timed out, for example from a broken line. Whether the drive trips is set in C076. The remote operator shows NET.ERR.^[1][4][5][6]

Also on: WJ200 (NT325DX): E41 Modbus communication error. SJ200 and X200 use E60 Communications error for a network timeout.

Likely causes

• Broken or loose communication cable
• Wrong communication speed setting
• Cable run too long

First checks, in this order

1. Check the communication speed setting (C071).
2. Check the wiring and the cable length.
3. Check the action on error (C076) and timeout (C077).

E041: RS485 communication error

What it means: RS485 communication (such as Modbus-RTU) timed out from noise, a loose connection or a broken line. CF-05 sets whether this is an error.^[2][3]

Also on: SJ700 (NT204DX): E41 Modbus communication error.

Likely causes

• Electrical noise
• Loose or broken communication cable
• Wrong communication settings

First checks, in this order

1. Check the wiring and connectors.
2. Separate the communication cable from power wiring.
3. Check the communication settings (CF-01 to CF-08) and the error action (CF-05).

E040: Operator keypad disconnection error

What it means: Communication with the keypad timed out from noise, a loose connection or a broken cable. UA-20 sets the action when the keypad is disconnected.^[2][3][6]

Also on: WJ200 (NT325DX): E40 Operator connection.

Likely causes

• Keypad unplugged or loose
• Damaged keypad cable
• Electrical noise

First checks, in this order

1. Check the keypad connection and cable.
2. Take noise countermeasures, such as separating the wiring.
3. Check UA-20.

E37: Emergency stop

What it means: With slide switch SW1 on the logic board set to ON, the EMR signal (terminal 3, normally closed) opened and the drive hardware shut off the output. A broken wire or wrong logic on terminal 3, or noise, also causes it. Only the RS signal on terminal 1 resets it, not the keypad. The remote operator shows EMR.^[1][5][6]

Also on: X200 (NT301XC): E37 Emergency Stop. WJ200 (NT325DX): E37 is Safe Stop.

Likely causes

• Emergency stop circuit opened by external equipment
• Terminal 3 not connected or its wire broken
• Wrong signal logic
• Noise on the EMR wiring

First checks, in this order

1. Find out why the external emergency stop opened and clear it.
2. Check the wiring and logic of intelligent input terminal 3.
3. Reset with the RS signal on terminal 1.
4. Remove noise sources near the drive.

E090 to E093: STO shutoff error, STO internal error, STO path 1 error, STO path 2 error

What it means: The safe torque off (STO) function found a problem in the functional safety circuit path. Hitachi refers to the separate Functional Safety Guide for details.^[2][3]

Likely causes

• Problem in the safety function system or STO wiring
• STO path 1 and path 2 inputs out of step

First checks, in this order

1. Check the STO wiring of both paths and the safety devices feeding them.
2. Follow the SJ-P1 Functional Safety Guide (NT2512) for the exact cause.

E38: Low-speed overload protection

What it means: An overload was detected while the motor ran at a very low speed (0.2 Hz or less), so the drive shut off its output. The trip history may record a higher frequency. The remote operator shows OL-LowSP.^[1][6]

Also on: WJ200 (NT325DX): E38 Low-speed overload protection.

Likely causes

• Motor load too high at very low speed

First checks, in this order

1. Reduce the load at very low speed.
2. If high torque near zero speed is needed, consider a larger drive.

E038: Low-speed range overload error

What it means: The built-in electronic thermal function detected an overload at 0.2 Hz or below and turned the output off to protect the main element.^[2][3]

Also on: SJ700 (NT204DX): E38 Low-speed overload protection.

Likely causes

• Heavy motor load at low speed

First checks, in this order

1. Reduce the load in the low-speed range.
2. If it happens often, choose a drive with more capacity for the motor.

E36: Braking error

What it means: With brake control on (b120 = 01), the drive did not receive the brake confirmation signal within the wait time (b124) after it sent the brake release signal. The remote operator shows BRAKE.^[1][6]

Also on: WJ200 (NT325DX): E36 Braking error.

Likely causes

• Brake not opening or closing
• Confirmation wait time (b124) too short
• Confirmation signal not wired or broken

First checks, in this order

1. Check that the brake actually opens and closes.
2. Increase the wait time (b124) if the brake is slow.
3. Check the wiring of the brake confirmation signal.

E036: Brake error

What it means: With the brake function on, the drive could not see the brake check signal (BOK) turn on or off within the wait time after it sent the brake release signal.^[2][3]

Also on: SJ700 (NT204DX): E36 Braking error.

Likely causes

• Broken brake check signal line
• Brake function settings or input logic not matched to the brake

First checks, in this order

1. Check the brake and the BOK signal wiring (dA-51 shows the input state).
2. Review the brake check wait times (AF134, AF141) and the input terminal logic.

E10: CT error

What it means: The internal current detector (CT) put out about 0.6 V or more at power-on, so the drive shut off its output. The remote operator shows CT. The drive also sets the major failure (MJA) signal.^[1][6]

Also on: WJ200 (NT325DX): E10 Current detection error.

Likely causes

• Failed current detector inside the drive

First checks, in this order

1. Cycle the power once to confirm.
2. If E10 returns, send the drive for repair.

E010: Current detector error

What it means: The built-in current detector had a problem, so the drive turned its output off. It is a serious fault: MJA turns on and RS does not clear it.^[2][3]

Also on: SJ700 (NT204DX): E10 CT error.

Likely causes

• Broken current detector circuit
• Electrical noise near the drive

First checks, in this order

1. Take noise countermeasures.
2. Cycle the power. If the error returns, the drive needs repair.

E11: CPU error

What it means: The internal CPU malfunctioned, so the drive shut off its output. Reading bad data from the EEPROM can also cause it. The remote operator shows CPU. Only a power cycle clears it.^[1][4][5][6]

Also on: SJ200 (NB650XA): E11 or E22 CPU error. X200 (NT301XC) and WJ200 (NT325DX): E11 CPU error.

Likely causes

• Electrical noise near the drive
• Failed control board

First checks, in this order

1. Remove or shield noise sources near the drive.
2. Cycle the power. If E11 returns, send the drive for repair.

E011: CPU error

What it means: The built-in CPU malfunctioned, so the drive turned its output off. If a power cycle does not clear it, the CPU is likely broken. It is a serious fault (MJA on).^[2][3]

Also on: SJ700 (NT204DX): E11 CPU error.

Likely causes

• Electrical noise
• Data inconsistency after a write was interrupted
• Broken CPU

First checks, in this order

1. Take noise countermeasures.
2. Cycle the power or initialize the drive; after it recovers, initialize and re-enter the parameters.
3. If it does not recover, send the drive for repair.

E23: Gate array communication error

What it means: Communication between the internal CPU and the gate array failed, so the drive tripped. The remote operator shows GA.COM. The drive also sets the major failure (MJA) signal.^[1][4]

Also on: SJ200 (NB650XA): E23 Gate array error.

Likely causes

• Electrical noise
• Internal communication cable disconnected

First checks, in this order

1. Remove noise sources near the drive.
2. Check the internal connectors, or send the drive for repair.

E25: Main circuit error

What it means: The gate array could not confirm the on and off state of the IGBTs, because of noise, a short circuit or a damaged main circuit element. The remote operator shows Main.Cir. Only a power cycle clears it.^[1][6]

Also on: WJ200 (NT325DX): E25 Main circuit error.

Likely causes

• Electrical noise
• Short circuit on the output
• Damaged IGBT or main circuit element

First checks, in this order

1. Remove noise sources near the drive.
2. Check the output circuit for a short circuit.
3. Have the IGBTs checked, or send the drive for repair.

E019: Temperature detector error

What it means: The temperature detector circuit is disconnected or broken. It is a serious fault (MJA on).^[2][3]

Likely causes

• Disconnected or broken temperature detector circuit
• Electrical noise

First checks, in this order

1. Take noise countermeasures and cycle the power.
2. If it keeps happening, send the drive for repair.

E042: RTC error

What it means: The real-time clock in the keypad went back to its initial data, usually because the keypad battery is flat.^[2][3]

Likely causes

• Dead keypad battery

First checks, in this order

1. Replace the keypad battery.
2. Set the date and time again.

E60: Option 1 error 0 (SJ-FB: Encoder disconnection; SJ-DG: SJ-DG error; SJ-DN: DeviceNet communication error)

What it means: An option board in slot 1 reported error 0. With the SJ-FB feedback board: encoder wiring disconnected, encoder failed or an encoder without line driver output. With the SJ-DG digital option board: communication timeout with the board. With the SJ-DN DeviceNet board: Bus-Off or timeout on DeviceNet (action set by P045 and P048). Remote operator: OP1-0.^[1][4][5]

Also on: On the SJ700 the same board in slot 2 shows E70. SJ200 (NB650XA) and X200 (NT301XC): E60 is Communications error (network watchdog timeout).

Likely causes

• Encoder cable broken or encoder failed (SJ-FB)
• Board not seated or DIP switch settings wrong
• DeviceNet cable, baud rate or network fault (SJ-DN)

First checks, in this order

1. Check that the option board is mounted correctly.
2. Check the encoder wiring and the SWENC DIP switches on the SJ-FB.
3. For DeviceNet, check the baud rate DIP switches, wiring distance and connections.
4. See the option board instruction manual.

E61: Option 1 error 1 (SJ-FB: Excessive speed; SJ-DN: Duplicate MAC ID)

What it means: With the SJ-FB board: motor speed reached maximum frequency (A004) times the over-speed detection level (P026). With the SJ-DN board: two or more devices on the network use the same MAC ID. Remote operator: OP1-1.^[1]

Also on: On the SJ700 the same board in slot 2 shows E71.

Likely causes

• Load overhauling the motor, or wrong encoder or speed settings (SJ-FB)
• Duplicate MAC ID on the DeviceNet network (SJ-DN)

First checks, in this order

1. Check A004 and P026, and the encoder settings.
2. Check the MAC ID DIP switches on every device on the network.

E62: Option 1 error 2 (SJ-FB: Positioning error; SJ-DN: External trip)

What it means: With the SJ-FB board in position control: the position error reached 1,000,000 pulses or more. With the SJ-DN board: the Force Fault/Trip bit (Attribute 17, Instance 1, Class 29) was set to 1. Remote operator: OP1-2.^[1]

Also on: On the SJ700 the same board in slot 2 shows E72.

Likely causes

• Load blocked or too heavy to follow the position command (SJ-FB)
• Network master set the force fault bit (SJ-DN)

First checks, in this order

1. Check the machine for jams and review the position control settings.
2. For DeviceNet, check Attribute 17 in Instance 1 of Class 29 and clear it to 0.

E63: Option 1 error 3 (SJ-FB: Position control range trip)

What it means: In absolute position control with the SJ-FB board, the current position went beyond the forward (P072) or reverse (P073) position range, so the drive tripped and the motor coasted. Remote operator: OP1-3.^[1]

Also on: On the SJ700 the same board in slot 2 shows E73.

Likely causes

• Position command or machine travel beyond the set range
• P072 or P073 set too small

First checks, in this order

1. Check the position range settings P072 and P073.
2. Check the position commands and the machine travel.

E69: Option 1 error 9 (SJ-FB: SJ-FB connection error; SJ-DN: Inverter communication error)

What it means: With the SJ-FB board: a faulty connection (mounting) of the feedback board was detected. With the SJ-DN board: communication between the drive and the DeviceNet board timed out. Remote operator: OP1-9.^[1]

Also on: On the SJ700 the same board in slot 2 shows E79.

Likely causes

• Option board loose or not seated
• Option board disconnected from the drive

First checks, in this order

1. Power off and reseat the option board.
2. Check the board connector and DIP switch settings.
3. See the option board instruction manual.

E70 to E79: Option 2 error

What it means: The option board in slot 2 (near the control terminal block) reported an error. The last digit has the same meaning as for slot 1 (E60 to E69) for that board. Remote operator: OP2-0 to OP2-9.^[1]

Likely causes

• Option board not mounted correctly
• Option board used or set up incorrectly

First checks, in this order

1. Check that the option board is mounted correctly.
2. Check the board settings against its instruction manual (SJ-FB, SJ-DG or SJ-DN).

E060 to E069: Option 1 errors 0 to 9

What it means: An error in the option mounted in option slot 1 (the left slot). The meaning of each number depends on the option.^[2][3]

Also on: SJ700 (NT204DX): E60 to E69 Option 1 error.

Likely causes

• Option not mounted securely
• Option used or set up incorrectly

First checks, in this order

1. Check that the option is mounted securely.
2. Look up the error number in the user's guide of that option.

E070 to E079: Option 2 errors 0 to 9

What it means: An error in the option mounted in option slot 2 (the center slot). The meaning of each number depends on the option.^[2][3]

Also on: SJ700 (NT204DX): E70 to E79 Option 2 error.

Likely causes

• Option not mounted securely
• Option used or set up incorrectly

First checks, in this order

1. Check that the option is mounted securely.
2. Look up the error number in the user's guide of that option.

E080 to E089: Option 3 errors 0 to 9

What it means: An error in the option mounted in option slot 3 (the right slot). The meaning of each number depends on the option.^[2][3]

Likely causes

• Option not mounted securely
• Option used or set up incorrectly

First checks, in this order

1. Check that the option is mounted securely.
2. Look up the error number in the user's guide of that option.

E094 to E097: FS option internal error, FS option path 1 error, FS option path 2 error, FS option connection error

What it means: The P1-FS functional safety option reported a problem in its circuit, one of its two paths or its connection.^[2][3]

Likely causes

• Problem in the safety function system wired to the P1-FS
• P1-FS option not connected properly

First checks, in this order

1. Check the P1-FS mounting and its safety wiring.
2. Follow the P1-FS Functional Safety Guide (NT2582) for the exact cause.

E100: Encoder disconnection error

What it means: The P1-FB feedback option detected a broken encoder signal line.^[2][3]

Also on: SJ700 with SJ-FB board: E60 (slot 1) or E70 (slot 2) Encoder disconnection.

Likely causes

• Encoder cable broken or unplugged
• Encoder failure

First checks, in this order

1. Check the encoder cable and connectors.
2. Check the encoder and the P1-FB switch settings (see the P1-FB User's Guide NT253).

E104: Position control range error

What it means: In position control, the current position went beyond the range set in AE-52 and AE-54.^[2][3]

Also on: SJ700 with SJ-FB board: E63 Position control range trip.

Likely causes

• Position command or machine travel beyond the set range
• Encoder or wiring problem

First checks, in this order

1. Check the position range settings AE-52 and AE-54.
2. Check the wiring, encoder settings and operating conditions.

E105: Speed deviation error

What it means: The difference between commanded and actual speed went above the speed deviation error detection level (bb-83).^[2][3]

Likely causes

• Load too heavy or machine binding
• Encoder or wiring problem
• Detection level or time set too tight

First checks, in this order

1. Check the machine and the load.
2. Check the encoder wiring and settings.
3. Review bb-82 and bb-83.

E106: Position deviation error

What it means: The position error went above the position deviation error detection level (bb-86).^[2][3]

Also on: SJ700 with SJ-FB board: E62 Positioning error.

Likely causes

• Machine jammed or too heavy to follow the command
• Encoder or wiring problem
• Detection level or time set too tight

First checks, in this order

1. Check the machine for jams.
2. Check the encoder wiring and settings.
3. Review bb-86 and bb-87.

E107: Over-speed error

What it means: Motor speed went above the over-speed detection level (bb-80).^[2][3]

Also on: SJ700 with SJ-FB board: E61 Excessive speed.

Likely causes

• Load driving the motor too fast
• Encoder or speed control problem
• Detection level set too low

First checks, in this order

1. Check the load and the speed control settings.
2. Check the encoder wiring and settings.
3. Review bb-80 and bb-81.

E110: Contactor error

What it means: The contactor control function found a fault in the external contactor sequence.^[2][3]

Likely causes

• External contactor wiring or feedback fault
• Contactor control settings wrong

First checks, in this order

1. Check the contactor control settings AF120 to AF123.
2. Check the wiring of the external contactor.

E112: FB option connection error

What it means: The P1-FB feedback option reported a connection error.^[2][3]

Also on: SJ700 with SJ-FB board: E69 SJ-FB connection error.

Likely causes

• P1-FB not mounted or connected properly

First checks, in this order

1. Power off and check the P1-FB mounting.
2. See the P1-FB User's Guide (NT253).

E120: PID start abnormality error

What it means: With PID soft start error detection set to trip (AH-81 = 01), the PID feedback stayed below the level in AH-82 after the soft start time (AH-80). Hitachi uses it to catch problems such as a broken pipe or a leak.^[2][3]

Likely causes

• Leak or broken pipe, so pressure or flow does not build up
• Feedback sensor or wiring fault
• Soft start time or detection level set too tight

First checks, in this order

1. Check the pipework and the process for leaks.
2. Check the feedback sensor and its wiring.
3. Review the PID soft start settings AH-75 to AH-82.

E43: Invalid instruction

What it means: The easy sequence (EzSQ) program contains an invalid instruction, or the PRG terminal was turned on with no program loaded. The remote operator shows PRG.CMD.^[1][6]

Also on: WJ200 (NT325DX): E43 EzSQ invalid instruction.

Likely causes

• Invalid instruction in the downloaded program
• PRG input on with no program loaded

First checks, in this order

1. Download the program again and check it for invalid instructions.
2. Check the PRG input.

E44: Nesting count error

What it means: Subroutines or for and next loops in the easy sequence program are nested more than eight levels deep. The remote operator shows PRG.NST.^[1][6]

Also on: WJ200 (NT325DX): E44 EzSQ nesting count error.

Likely causes

• Program nested more than eight levels

First checks, in this order

1. Restructure the program to reduce nesting.

E45: Execution error 1

What it means: The easy sequence program hit an execution error: a go to target without its nest start, an overflow, underflow or division by zero, or a chg param or mon param instruction using an undefined parameter, an out-of-range value or a parameter that cannot change while running. The remote operator shows PRG.ERR1.^[1][6]

Also on: WJ200 (NT325DX): E45 EzSQ instruction error.

Likely causes

• Program flow error (for and next order)
• Arithmetic overflow, underflow or division by zero
• Wrong parameter access in chg param or mon param

First checks, in this order

1. Check the for and next structure and the go to targets.
2. Check the arithmetic results.
3. Check the parameters and values used by chg param and mon param.

E50 to E59: User trips 0 to 9

What it means: The easy sequence program ran a trip instruction set by the programmer. The remote operator shows PRG-0 to PRG-9.^[1]

Likely causes

• Condition programmed by the machine builder in the EzSQ program

First checks, in this order

1. Check the trip instructions in the program to see which condition sets this number.
2. Ask the machine builder what the user trip means for this machine.

E043: EzSQ illegal instruction error

What it means: The EzSQ program has an invalid instruction, or the program was started with no program written.^[2][3]

Also on: SJ700 (NT204DX): E43 Invalid instruction.

Likely causes

• Program not written (factory default or after initialization)
• Write error from electrical noise

First checks, in this order

1. Write the EzSQ program to the drive.
2. Remove noise sources and write the program again.

E044: EzSQ nest count error

What it means: Subroutines or for and next statements in the EzSQ program are nested more than 8 times.^[2][3]

Also on: SJ700 (NT204DX): E44 Nesting count error.

Likely causes

• Program structure too complex

First checks, in this order

1. Restructure the program to reduce nesting.

E045: EzSQ executive instruction error

What it means: The EzSQ program stopped on an execution error: overflow, underflow or division by zero, a broken for and next structure, or chg param or mon param using a parameter that does not exist or a value out of range.^[2][3]

Also on: SJ700 (NT204DX): E45 Execution error 1.

Likely causes

• Problem in the program data
• Wrong program flow
• Wrong parameter access

First checks, in this order

1. Check the arithmetic results.
2. Check the for and next structure and the go to targets.
3. Check the chg param and mon param instructions.

E050 to E059: EzSQ user-assigned errors 0 to 9

What it means: The EzSQ program ran a user-assigned trip instruction.^[2][3]

Also on: SJ700 (NT204DX): E50 to E59 User trips 0 to 9.

Likely causes

• Condition programmed in the EzSQ program

First checks, in this order

1. Check the trip instructions in the program and correct them if the trip was not intended.
2. Ask the machine builder what the user trip means for this machine.