The Lenze 9300 servo inverter family controls variable-speed drives with PM synchronous motors, asynchronous standard motors and asynchronous servo motors, and many of these drives are still in service. When one of these drives trips, the keypad or the history buffer shows a short display code such as OC1, OU, LU or Sd2. This guide explains what each code means and how to reset a trip. It also shows how to tell a wiring, motor or setup problem from a controller that needs repair. All codes, thresholds and ratings come from Lenze's 9300 servo inverter System Manual EDSVS9332S (EN 6.0-07/2013) and related Lenze documents. Flexa Systems is an independent supplier that sells new and refurbished automation parts and repairs drives at component level. We currently offer a refurbished EVS9328-ES servo inverter and repair the wider EVS93xx and EVF93xx range.
Reading a 9300 Type Code: EVS9328-ES Decoded
Before you troubleshoot, confirm exactly which 9300 you have. The nameplate on a 9300 servo inverter follows this pattern (EDSVS9332S, p. 1.1-3):
EVS 93xx - x x Vxx 6x 8x
- EVS: product range, servo controller. Lenze treats this as one three-letter code and does not define the individual letters. The 9300 vector frequency inverter uses EVF instead.
- 93xx: type number, which sets the rated power (9321 through 9332 for the servo).
- First letter after the dash (design): E = built-in unit (IP20, panel-mounted), C = built-in unit in "cold plate" technology.
- Second letter after the dash (version): S = servo inverter, P = positioning controller, K = cam profiler, R = register controller. Lenze also lists EVS93XX-xI and EVS93XX-xT as the "9300 Servo PLC" (as of hardware 7A, software 8.0). For the 9300 vector, V = vector-controlled frequency inverter (EVF93xx-EV).
- Vxxx (variant): no suffix = standard; V003 = cold plate; V004 = with "safe torque off"; V100 = for IT mains; V104 = with "safe torque off" and for IT mains.
- 6x / 8x: hardware version and software version.
Decoded, EVS9328-ES is a 9300 servo controller, type 9328, built-in unit (E), servo inverter version (S), standard variant with no Vxxx suffix. Type 9328 is rated 22 kW at 400 V and 30 kW at 480 V.
The version letter matters for fault-finding. The servo position controller (EDSVS9332P), servo cam profiler (EDSVS9332K), Servo PLC and 9300 vector (EDSVF9333V) each have their own manual. Their function blocks and some monitoring differ from the servo inverter. The 9300 vector also extends to type 9333 and uses different 480 V power ratings for types 9330 to 9332. A replacement or repaired unit must match the version letter and variant. A safe torque off variant (V004/V104) cannot be swapped for a standard unit without losing that function.
9300 Servo Ratings at 400 V
The table below reproduces the rated data for the EVS93xx-xS servo inverter at 400 V mains (EDSVS9332S, ch. 3.3). The mains range is 3/PE AC 320 V −0 % to 440 V +0 %, 45 Hz −0 % to 65 Hz +0 %. A DC supply of 450 V −0 % to 620 V +0 % is the alternative.
| Type | Mains current with choke [A] | Motor power [kW / hp] | Output Sr8 [kVA] | Ir8 [A] | IM8 [A] | Ir16 [A] | Power loss [W] |
|---|---|---|---|---|---|---|---|
| EVS9321-xS | 1.5 | 0.37 / 0.5 | 1.0 | 1.5 | 2.25 | 1.1 | 100 |
| EVS9322-xS | 2.5 | 0.75 / 1.0 | 1.7 | 2.5 | 3.75 | 1.8 | 110 |
| EVS9323-xS | 3.9 | 1.5 / 2.0 | 2.7 | 3.9 | 5.85 | 2.9 | 140 |
| EVS9324-xS | 7.0 | 3.0 / 4.0 | 4.8 | 7.0 | 10.5 | 5.2 | 200 |
| EVS9325-xS | 12.0 | 5.5 / 7.5 | 9.0 | 13.0 | 19.5 | 9.7 | 260 |
| EVS9326-xS | 20.5 | 11.0 / 15.0 | 16.3 | 23.5 | 35.3 | 15.3 | 390 |
| EVS9327-xS | 27.0 | 15.0 / 20.0 | 22.2 | 32.0 | 48.0 | 20.8 | 430 |
| EVS9328-xS | 44.0 | 22.0 / 30.0 | 32.6 | 47.0 | 70.5 | 30.6 | 640 |
| EVS9329-xS | 53.0 | 30.0 / 40.0 | 40.9 | 59.0 | 88.5 | 38.0 | 810 |
| EVS9330-xS | 78.0 | 45.0 / 60.0 | 61.6 | 89.0 | 133.5 | 58.0 | 1100 |
| EVS9331-xS | 100 | 55.0 / 75.0 | 76.2 | 110 | 165 | 70.0 | 1470 |
| EVS9332-xS | 135 | 75.0 / 100 | 100.5 | 145 | see note | 90.0 | 1960 |
Ir8 is the rated output current at 8 kHz, IM8 the maximum current at 8 kHz and Ir16 the rated current at 16 kHz. The maximum current applies to a periodic load cycle of no more than 1 minute of overcurrent followed by 2 minutes of base load at no more than 75 % Ir. The EVS9332-xS maximum current is omitted because the manual's printed value contains a typo.
Three related points from the same manual:
- EVS9324, EVS9326 and EVS9328 through EVS9332 may only be operated with the prescribed mains chokes and mains filters.
- At 480 V, the EVS9328-xS is rated 30.0 kW / 40.0 hp, 37.0 kVA, Ir8 44.7 A, IM8 67.1 A and Ir16 28.2 A, with 640 W power loss.
- The drive is cULus approved as Power Conversion Equipment (UL File No. E132659), with IP20 enclosure.
Lenze 9300 Fault Messages with Meaning and Remedy
Every 9300 monitoring function triggers one of four responses:
- TRIP (highest priority): outputs U, V and W switch to high resistance until the TRIP is reset, so the motor coasts with no control. The manual describes post-reset behavior in two ways. Section 8.2.1 says the drive accelerates to its setpoint on the set ramps. Section 9.3.2 says it remains at standstill. Verify how your machine behaves before resetting.
- Message: outputs are high resistance while the message is active. If the message lasts 0.5 s or less, the drive then accelerates to its setpoint with maximum torque. If it lasts longer, the drive coasts under internal controller inhibit. The drive restarts automatically once the message clears, and the manual flags this as a danger.
- Warning: display only. The drive keeps running under control.
- Off: no response. The manual warns that the drive can be destroyed if relevant monitoring is switched off.
The No. column shows the error number reported over the system bus (CAN) and stored in the history buffer. Its first digit is the response: 0 = TRIP, 1 = Message, 2 = Warning. A fixed first digit means the response cannot be changed. An "x" means you can set the response with the listed code, typically with "3" to switch monitoring off. For example, 2091 is an EEr reported as a warning. When several faults occur at once, only the one with the highest-priority response goes into the history buffer.
Codes and meanings can vary by model, firmware and catalog number, so confirm against the drive's own manual before acting.
Overcurrent and Overload
| Display | No. | Meaning | Cause and remedy | Default response / code |
|---|---|---|---|---|
| OC1 | 0011 | Short circuit of motor cable | Short circuit: search for cause, check motor cable. Excessive capacitive charging current: use a shorter motor cable or one with lower capacitance. | TRIP (fixed) |
| OC2 | 0012 | Motor cable earth fault | One motor phase has earth contact: search for cause, check motor cable. | TRIP (fixed) |
| OC5 | 0015 | I x t overload | Frequent or too long acceleration with overcurrent, or continuous overload above 1.05 x Irx: check drive dimensioning. Releases when C0064 > 100 %. Reset is only possible once C0064 < 95 %. | TRIP (fixed) |
| OC6 | 0016 | I²xt overload (motor) | Frequent or too long acceleration with motor overcurrent, or permanent motor overload: check drive dimensioning. | TRIP (fixed) |
| OC8 | x018 | I²xt overload advance warning | Same causes as OC6: check drive dimensioning. | Warning; C0606 |
| LP1 | x032 | Motor phase failure | Current-carrying motor phase failed: check motor and cable, or switch off (C0597 = 3). Current limit too low: raise via C0599. Usable for asynchronous motors only. | Off; C0597 |
| nErr | x190 | Speed control error (outside tolerance C0576) | Active load too high (for example a hoist) or mechanical blockage: check dimensioning. | Off; C0579 |
| NMAX | x200 | Maximum system speed (C0596) exceeded | Active load too high, or drive not speed-controlled with torque excessively limited: check dimensioning, raise torque limit, or switch off (C0607 = 3). | TRIP; C0607 |
DC Bus and Mains
| Display | No. | Meaning | Cause and remedy | Default response / code |
|---|---|---|---|---|
| OU | 1020 | Overvoltage in DC bus (above C0173 threshold) | Braking energy too high: use a braking unit or regenerative module, check brake resistor dimensioning. | Message (fixed) |
| LU | 1030 | Undervoltage in DC bus (below C0173 threshold) | Check mains voltage and supply cable. | Message (fixed) |
With the Lenze setting C0173 = 1 (400 V mains), LU sets at 285 V DC and resets at 430 V DC. OU sets at 770 V DC and resets at 755 V DC. With C0173 = 4 (480 V mains with braking unit), OU sets at 800 V DC. On a 480 V plant supply, check that C0173 matches the actual mains, because the OU and LU thresholds depend on it. OU and LU are Messages, so the drive restarts on its own when the bus voltage returns to range. Keep that in mind before anyone reaches into the machine.
Temperature
| Display | No. | Meaning | Cause and remedy | Default response / code |
|---|---|---|---|---|
| OH | 0050 | Heatsink temperature too high (table 9.3 lists > +90 °C; section 8.2.9 gives a fixed 85 °C threshold, reset at 80 °C) | Ambient above +40 °C or +50 °C: let it cool, improve ventilation, check cabinet temperature. Dirty heatsink: clean it. Wrong mounting position: change it. | TRIP (fixed) |
| OH3 | x053 | Motor temperature > +150 °C (via resolver or incremental encoder) | Motor thermally overloaded: check dimensioning or switch off (C0583 = 3). No PTC or thermal contact connected: correct wiring. | Off; C0583 |
| OH4 | x054 | Heatsink temperature > C0122 | As for OH. C0122 too low: enter a higher value. Can be switched off (C0582 = 3). | Warning; C0582 |
| OH7 | x057 | Motor temperature > C0121 | Motor thermally overloaded: check dimensioning. C0121 too low: raise it. Can be switched off (C0584 = 3). | Warning; C0584 |
| OH8 | x058 | Motor temperature via T1/T2 too high | Motor thermally overloaded: check dimensioning. T1/T2 not connected: connect PTC or thermal contact. Can be switched off (C0585 = 3). | Off; C0585 |
| H10 | x110 | Heatsink temperature sensor error | Sensor gives undefined values: contact Lenze. Switching off (C0588 = 3) is only permitted by Lenze service. | TRIP; C0588 |
| H11 | x111 | Temperature sensor error inside the controller | As H10. | TRIP; C0588 |
Feedback
The Lenze default feedback is a resolver at X7 (C0025 = 10). The resolver needs 1 pole pair and a transmission ratio of 0.3. The drive supplies it at 4 kHz and monitors it for open circuit. X8 accepts TTL incremental, SinCos and SinCos absolute encoders.
| Display | No. | Meaning | Cause and remedy | Default response / code |
|---|---|---|---|---|
| Sd2 | x082 | Resolver error at X7 | Resolver cable interrupted: check cable for open circuit, check resolver. Can be switched off (C0586 = 3). The manual warns that with Warning (C0586 = 2) the drive can be destroyed. | TRIP; C0586 |
| Sd3 | x083 | Encoder error at X9 (digital frequency coupling interrupted) | Cable interrupted: check cable. X9/8 not connected: apply 5 V to X9/8 or switch off (C0587 = 3). | TRIP; C0587 |
| Sd5 | x085 | Encoder error at X6/1 and X6/2 (C0034 = 1) | Current signal < 2 mA: check cable and encoder. Can be switched off (C0598 = 3). | Off; C0598 |
| Sd6 | x086 | Motor temperature sensor error (X7 or X8) | Sensor gives undefined values: check cable connection. Can be switched off (C0594 = 3). | Off; C0594 |
| Sd7 | x087 | Absolute value encoder: initialisation needed after C0025/C0420 change, initialisation error at X8, or communication error during rotor position adjustment | Save parameters, deenergise and switch on again. Check X8 cable and encoder, set C0421 to 8.0 V, use a Stegmann encoder or replace a defective one. A new rotor position adjustment is mandatory after Sd7, otherwise uncontrolled movements are possible. | TRIP (fixed) |
| Sd8 | x088 | SinCos encoder at X8 sends inconsistent data or no data | Damaged tracks: replace encoder. Interference: check shield, use the filter time constant. Open circuit, non-Stegmann or defective encoder, wrong supply voltage (C0421): fix, then deenergise completely. | Section 8.3 lists Off; section 6.6 lists TRIP as Lenze setting. Check C0580. |
| PL | x089 | Error during rotor position adjustment | Adjustment cancelled, or Sd7/Sd8 occurred during adjustment: repeat rotor position adjustment. | TRIP (fixed) |
| P03 | x153 | Following error | Angle difference above C0255: raise C0255 or switch off (C0589 = 3). Drive cannot follow digital frequency (Imax limit): check dimensioning. | Warning; C0589 |
| P13 | x163 | Angle overrun | Phase controller limit reached, or drive cannot follow the digital frequency: enable drive, check dimensioning. | TRIP; C0590 |
| P19 | x169 | Input values at X9 are limited | Increments lost: reduce the frequency. Slave C0425 and master C0030 must be identical. | Warning; C1292 |
Communication
| Display | No. | Meaning | Cause and remedy | Default response / code |
|---|---|---|---|---|
| CE0 | x061 | Automation interface (AIF) communication error | Plug the communication module or keypad XT in firmly and screw it down. Can be switched off (C0126 = 3). | Off; C0126 |
| CE1 | x062 | Communication error on CAN1_IN | Check wiring at X4 and the sender. Increase C0357/1 or switch off (C0591 = 3). | Off; C0591 |
| CE2 | x063 | Communication error on CAN2_IN | As CE1 (C0357/2; C0592 = 3). | Off; C0592 |
| CE3 | x064 | Communication error on CAN3_IN | As CE1 (C0357/3; C0593 = 3). | Off; C0593 |
| CE4 | x065 | BUS-OFF state of system bus (CAN) | Check X4 wiring, bus termination, shield and PE. Check bus load and reduce baud rate if needed. Can be switched off (C0595 = 3). | Off; C0595 |
| P16 | x166 | Faulty transfer of CAN sync telegram | Sync out of cycle: set C1121 (C0362 shows the interval; 0 = interrupted). Sync not received: check channel, baud rate, address. Controller enabled too fast: delay enable. | Off; C1290 |
Parameter and System
| Display | No. | Meaning | Cause and remedy | Default response / code |
|---|---|---|---|---|
| CCr | 0071 | System failure | Strong interference on control cables: screen them. Ground or earth loops: check wiring and PE. Then deenergise completely (disconnect 24 V, discharge DC bus). | TRIP (fixed) |
| PR1 | 0072 | Checksum error in parameter set 1 (Lenze setting loaded automatically) | Fault when loading or interrupted keypad transfer, or parameters incompatible with software version: set parameters and store under C0003 = 1. | TRIP (fixed) |
| PEr | 0074 | Program error | Send parameter set and description to Lenze, then deenergise completely. | TRIP (fixed) |
| PR0 | 0075 | Error in parameter set | Operating system software updated: store Lenze setting (C0003 = 1), then deenergise completely. | TRIP (fixed) |
| PI | 0079 | Fault during parameter initialisation | Transfer error between devices, or parameter set does not match the controller (for example from a higher-power to a lower-power unit): correct the parameter set or send it to Lenze. | TRIP (fixed) |
| EEr | x091 | External monitoring triggered via DCTRL (TRIP-SET) | A digital signal assigned to TRIP-SET was activated: check the external encoder. Can be switched off (C0581 = 3). | TRIP; C0581 |
| H05 | 0105 | Internal fault (memory) | Contact Lenze. | TRIP (fixed) |
| H07 | 0107 | Internal fault (power stage) | Incorrect power stage detected during initialisation: contact Lenze. | TRIP (fixed) |
If you also maintain newer Lenze inverters, our guide to Lenze 8400 fault codes covers that platform. Its codes are not interchangeable with the 9300.
How to Reset a 9300 Trip
A pending TRIP cannot be reset while its source is still active, so remove the cause first. EDSVS9332S and the 9300 servo Operating Instructions (EDB9300UES) list these reset methods:
- Keypad XT EMZ9371BC: remove the cause, press STOP, then press RUN.
- Code C0043 = 0.
- Control word C0135, bit 11.
- AIF control word from a fieldbus module on X1.
- System bus (CAN) control word.
- Terminal X5/E5: with the Lenze terminal configuration, a LOW-HIGH edge on E5 resets the trip.
- Global Drive Control (GDC): click "TRIP reset" in the Diagnostics dialog.
Messages (such as OU and LU) and Warnings clear by themselves once the fault is gone. After a Message clears, the drive restarts automatically. For CCr, PEr, PR0, Sd7 and Sd8, the remedy also requires complete deenergising: disconnect the 24 V supply and discharge the DC bus.
Before you reset anything, record the history buffer. It holds 8 entries, from the active fault back to the seventh-last. C0168 shows the fault, C0169 the time and C0170 the frequency, and C0067 shows the current trip. The buffer can only be cleared when no fault is active. The controller LEDs also help:
- Red off and green on: enabled.
- Red on and green on: mains on, auto-start inhibited.
- Green blinking slowly: controller inhibited.
- Red blinking quickly: undervoltage or overvoltage.
- Red blinking slowly: fault active.
Faults That Point to a Failed Controller vs. Wiring, Motor or Setup
Most 9300 trips are caused outside the drive. The manual's remedies lead to cables, motors, braking resistors, parameters or cabinet conditions. A few patterns, however, point strongly to the controller itself.
Likely a Controller Problem
- CCr that returns after control cables have been screened, PE and earth loops checked, and the drive fully deenergised.
- PEr, especially if it recurs after deenergising. Lenze's own remedy is to send the parameter set to Lenze.
- PR0, PR1 or PI that come back after a correct parameter set has been stored with C0003 = 1 and power cycled. If saved parameters do not survive a power cycle, suspect memory or control board faults.
- H05, H07, H10 and H11. The manual's only remedy is to contact Lenze, which means these faults are internal.
- OH with a clean heatsink and normal ambient. The rated operating range is 0 to +55 °C for EVS9321 through EVS9326 and 0 to +50 °C for EVS9327 through EVS9332, with a 2.5 %/°C current derating above +40 °C. If the heatsink is clean, the mounting position is correct and the cabinet is within range, the fans or temperature sensing inside the drive are suspect.
- OC1 or OC2 with the motor cable proven good. Disconnect the motor at U, V and W and megger the cable and motor separately. If OC1 or OC2 returns immediately on enable with the motor leads removed, the fault is inside the power stage.
Likely Wiring, Motor or Setup
- OU on deceleration: brake resistor, braking unit or C0173 setting.
- LU: mains voltage, supply cable, fuses, or a weak supply during start-up.
- OC5 and OC6: drive or motor dimensioning, acceleration times or mechanical binding.
- Sd2, Sd3, Sd6, Sd7, Sd8: feedback cables, connectors, encoder type and supply voltage.
- CE0 to CE4 and P16: module seating, X4 wiring, termination, baud rate.
- OH3, OH7, OH8: motor thermal load or missing PTC wiring.
- EEr: an external device wired to TRIP-SET.
Do not leave monitoring switched off as a "fix." The manual warns that the Off response, and Warning on Sd2, can destroy the drive. Also remember that safe torque off (V004/V104 variants only) is not an emergency stop. There is no electrical isolation between motor and controller, so lock out and discharge the DC bus before working on motor wiring. For a broader view of the decision, see our article on servo repair vs replacement. Our write-up on what fails inside drives explains which components we see on the bench.
Repair or Refurbished: Keeping a 9300 Line Running
Lenze's US website now lists the 9300 servo inverters and 9300 vector frequency inverters under "Previous products." For plants with these drives on critical machines, the practical options are component-level repair of the existing unit or a refurbished replacement with the same type code, version letter and variant. Matching the type code keeps the parameter set, I/O wiring, resolver feedback and fieldbus module (LECOM, PROFIBUS-DP, INTERBUS, DeviceNet/CANopen or LON on the AIF interface) usable without re-engineering. It also avoids the PI fault, which the manual links to a parameter set that does not match the controller, for example one transferred from a higher-power to a lower-power unit.
Flexa Systems offers both paths:
- Refurbished replacement: a refurbished EVS9328-ES is available. You can order the refurbished 22 kW 9300 servo inverter as a spare or swap unit while the original is repaired.
- Repair: our Lenze drive repair service covers the EVS9328-ES and other EVS93xx and EVF93xx type numbers. Repairs are carried out at component level, and units are tested before return. For other type numbers, we quote on request. We do not claim them as stock.
Repair and refurbished replacement carry equal weight here. Repair keeps your own unit and its history. A refurbished spare shortens downtime when the line cannot wait. Many plants do both: install the refurbished unit, then repair the failed one as the next shelf spare. Repairs and refurbished units from Flexa include a 2-year warranty; see our warranty coverage details for terms. If a line is down, ask about our rush repair service.
When you send a 9300 in, include the full nameplate (type code, hardware and software version), the history buffer contents from C0168, and a note on whether the fault returns with the motor disconnected. That information speeds diagnosis. For other drive brands on the same machine, see our general servo drive repair service. You can also browse servo drives for sale and our Lenze parts catalog. If your plant also runs newer Lenze servo hardware, our page for the Lenze 9400 E94AMPE0074 servo lists that unit separately. It is a different platform, not a direct swap for a 9300.
To get a 9300 evaluated, request a quote online or call Flexa Systems at (254) 254-0005.
Frequently Asked Questions
What does OC1 mean on a Lenze 9300 servo inverter?
OC1 (number 0011) means short circuit of the motor cable, and the response is a fixed TRIP. Lenze lists two causes: an actual short circuit, or excessive capacitive charging current in a long or high-capacitance motor cable. Check the motor and cable separately. If OC1 returns with the motor leads disconnected, the power stage is suspect.
Why does my 9300 show Sd2?
Sd2 (x082) is a resolver error at X7, typically an interrupted resolver cable. The Lenze default response is TRIP, set with C0586. Check the cable, connectors and the resolver itself. Lenze warns that setting C0586 to Warning can destroy the drive, so repair the feedback path rather than reducing the response.
Will a 9300 restart by itself after OU or LU?
Yes. OU and LU are fixed Message responses. The outputs go to high resistance while the message is active. Once the DC bus voltage is back in range, the message clears and the drive restarts automatically. Lenze flags this as a danger, so treat the machine as live while OU or LU is displayed.
How do I reset a TRIP on a 9300?
First remove the cause, because a TRIP cannot be reset while its source is active. Then press STOP and RUN on the XT EMZ9371BC keypad, set C0043 = 0, use C0135 bit 11 or a fieldbus or CAN control word, apply a LOW-HIGH edge on X5/E5 with the Lenze terminal configuration, or use TRIP reset in GDC.
Should I repair my 9300 or buy a refurbished unit?
Both work, and Flexa offers both. A refurbished EVS9328-ES is available as a replacement, and we repair the EVS9328-ES and other EVS93xx and EVF93xx units at component level, quoting other type numbers on request. Repairs and refurbished units come with a 2-year warranty. A refurbished spare minimizes downtime while the original is repaired.
