Yaskawa GA800 E22 Error Code — What It Means
E22 on the Yaskawa GA800 variable frequency drive indicates a serial communication transmission error. The drive has detected a problem in the communication line between the controller and the VFD. This is not a motor or power problem. It is a control signal or network path fault. The documented corrective action is to locate and repair wiring errors, disconnected cables, or short circuits in the serial communication cable.
Common Causes
- Incorrect communication cable wiring Reversed conductors, wrong terminal assignments, or improper cable routing can prevent the drive from receiving clean serial data.
- Disconnected or open cable A broken wire, loose terminal, or unplugged connector in the serial communication circuit stops transmission and triggers the fault.
- Short circuit in the communication cable Damaged insulation or pinched wires that create a short between conductors or to ground will corrupt the signal.
- Communication option card or network switch issue If the drive uses a network option board, a fault in the card, its wiring, or the upstream switch or gateway can appear as E22.
- Faulty control board communication interface If wiring and cables are intact, the drive’s control board communication circuit may have failed and require replacement.
Step-by-Step Fix
- Confirm the fault code by checking the keypad or operator display to verify it reads E22 and not a different communication alarm.
- Inspect the serial communication cable at both the drive and controller ends for loose terminals, reversed wires, damaged insulation, or broken conductors.
- Test the cable for opens and shorts using a multimeter to check continuity and isolation between conductors and from each conductor to ground.
- Check network option wiring and connections if the drive uses an option card or fieldbus module, and inspect any upstream switches or gateways for link status.
- Correct any wiring errors by re-terminating cables to match the wiring diagram, and repair or replace any damaged cable sections.
- Clear the fault from the drive keypad and cycle power if needed, then monitor the communication link to confirm the alarm does not return.
- Escalate to control board diagnosis if the fault persists after cable and wiring repair, as the issue may be in the drive’s communication interface hardware rather than field wiring.
Parts Often Needed
| Part | Notes |
|---|---|
| Serial communication cable (shielded twisted-pair) | Amazon | Match the cable type and gauge to your communication protocol and distance per the GA800 installation manual. |
| Communication option board or module | Amazon | If the drive uses a network option card (DeviceNet, Profibus, Ethernet/IP), confirm the part number with your drive serial tag. |
| GA800 control board | Amazon | Replacement for the drive’s internal control circuit if wiring is intact but communication faults persist. |
When to Call a Pro
Call a qualified industrial technician or Yaskawa-authorized service provider if you cannot locate a wiring fault in the communication cable and the alarm returns after repairs. Communication faults that remain after correct wiring and cable replacement usually indicate a drive control board or option card failure that requires bench-level diagnosis and replacement. Have the drive model number, serial number, and a description of the communication setup (protocol, option cards, controller type) ready when you contact support.