Troubleshooting a Unidrive with Hardware Fault Trip Codes

Unidrive Classics are going to trip at one time or another. Refer to this list of Unidrive trip codes next time your Uni1405 or other Unidrive is throwing a mysterious trip error.

HF81 – Software Error (odd address word)
HF82 – Large option module removed
HF83 – Power Board Code Failure
HF84 – Current Offset Trim Failure
HF85 – A to D failure (ES-CC step)
HF86 – Interrupt Watchdog failure
HF87 – Internal ROM check error
HF88 – Watchdog Failure
HF89 – Unused Interrupts (nmi as source)
HF90 – Stack Overflow
HF91 – Stack Underflow
HF92 – Software Error (undefined op code)
HF93 – Software Error (protection fault)
HF94 – Software Error (odd address word)
HF95 – Software Error (odd address inst.)
HF96 – Software Error (illegal ext bus)
HF97 – Level 1 Noise
HF98 – Interrupt Crash
HF99 – Level 1 Crash

A few notes on these Unidrive trip codes:

• HF trips are internal hardware faults within the drive. Powering the drive down and re-applying power could clear the fault.
• Resetting the drive will not clear a HF trip.
• If a HF trip occurs, the Drive Healthy relay will open to indicate this
• The serial communications will not function during a HF trip
• The only HF trip that can be caused by the user is a HF82 trip where a
  large option module is removed while the drive is powered up.The drive should be powered down, the module re-fitted correctly and the power reapplied to clear the trip

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