OMRON 3G3MV Inverter Practical Guide

Used for precise positioning when stopping or to "capture" the rotating motor before starting.

Parameter Name Range Factory Value Description

N089 DC braking current 0-100% 50% at the rated current of the frequency converter of 100%

DC braking time during n090 stop: 0.0-25.5s 0.5s. After deceleration and stop, inject DC braking

DC braking time during n091 startup: 0.0-25.5s. Inject DC braking before startup to prevent reverse rotation

7. Carrier frequency and derating (n080)

The carrier frequency affects motor noise, frequency converter losses, and external interference. Set ranges 1-4 and 7-9, with specific values depending on the capacity. The default value is usually 4 (approximately 10kHz). Attention: If the cable between the frequency converter and the motor is long (>100m), the carrier frequency should be reduced to minimize leakage current and reflected waves. The 5.5-7.5kW model can also enable the low-speed carrier frequency reduction function (n175), which automatically reduces the carrier frequency to 2.5kHz when the output frequency is ≤ 5Hz and the output current is ≥ 110%, improving the low-frequency overload capacity.

8. Multi functional input/output configuration (n050-n059)

Multi functional inputs S1-S7 can assign functions (1-33), default value:

N050 (S1)=1 (forward rotation/stop)

N051 (S2)=2 (reverse/stop)

N052 (S3)=3 (external fault NO)

N053 (S4)=5 (fault reset)

N054 (S5)=6 (multi-stage speed 1)

N055 (S6)=7 (multi-stage speed 2)

N056 (S7)=8 (jog)

Common function codes: 1=forward/stop, 2=reverse/stop, 3/4=external fault, 5=fault reset, 6/7=multi-stage speed, 8=jog, 9=acceleration/deceleration prohibition, 10=local/remote selection, 11=acceleration/deceleration time selection 1, 12=emergency stop, 13=multi-stage speed 3, 27=acceleration/deceleration time selection 2, etc.

Multi functional outputs (n057 MA/MB/MC, n058 P1-PC, n059 P2-PC) can be assigned 0-21 functions, default:

N057=0 (fault output)

N058=1 (in operation)

N059=2 (consistent frequency)

9. Vector control and motor parameters (n106-n110, etc.)

When n002=1 (vector control), the following parameters need to be set correctly to achieve optimal performance:

N036: Rated motor current

N106: Rated motor slip

N107: Motor phase to phase resistance (or half of the line to line resistance)

N108: Motor leakage inductance

N110: Motor no-load current (as a percentage of rated current)

These parameters are pre-set according to standard motors when they leave the factory and usually do not need to be adjusted, but they should be reset when replacing special motors.

10. PID control (n128-n138)

3G3MV built-in PID regulator, suitable for constant pressure water supply, air volume control, etc. Set n128=1-8 (select PID control method), with the following parameters:

N130: Proportional gain (P)

N131: Integral time (I)

N132: Differential time (D)

N129: Feedback value gain

N136-n138: Feedback loss detection

11. Communication parameters (n151-n157)

Supports RS-422/485 Modbus protocol (optional or built-in). Key parameters:

N153: Slave address (1-32)

N154: Baud rate (0=2400,1=4800,2=9600,3=19200)

N155: Parity check (0=even, 1=odd, 2=none)

N151: Communication timeout handling (0-4)

Troubleshooting: Systematic Diagnostic Process

3G3MV has complete protection functions. When there is a fault, the digital operator displays an error code, the fault relay acts, and the motor slides freely to stop. The following are common faults and countermeasures.

1. Fatal Error

Display Name Common Reasons Corrective Actions

OC overcurrent output short circuit, grounding, high V/f, excessive motor capacity check motor cable; Reduce V/f voltage; Extend acceleration and deceleration time

OU overvoltage deceleration too fast, no braking resistor, high power supply voltage connected to braking resistor; Extend deceleration time; Set n092=1 to prohibit stall prevention during deceleration

UV1 main circuit undervoltage phase loss, loose terminals, and instantaneous power outage inspection power supply; Set n081 instantaneous power outage compensation

OH radiator overheating environment with high temperature, heavy load, and fan failure to improve ventilation; Reduce load; Replace the cooling fan

OL1 motor overload, excessive load, improper V/f, n036 setting error to reduce load; Reduce V/f voltage; Check the rated current of the motor

OL2 frequency converter overload, heavy load, short acceleration time to reduce load; Extend acceleration time; Increase the capacity of the frequency converter

EF □ External fault multifunctional input terminal receives external fault signal to eliminate the cause of external fault; Check the NO/NC contact settings

F00/F01 digital operator communication failure. Poor or damaged contact of the operator. Reinstall the operator; Replace the operator

CE communication timeout RS-422/485 line fault, terminal resistance setting error check circuit; Set SW2-1 correctly; Check the main station program

PF/LF/GF/SC input phase loss/output phase loss/grounding/load short circuit power supply phase loss, motor disconnection, insulation damage inspection of main circuit wiring; Measure the insulation of the motor; Reduce the carrier frequency