90 H
Number of output ON times alarm detection count reached
Mitsubishi Electric · MELSEC iQ-R I/O Module
What does 90 H mean?
The number of output ON times has reached the pre-configured alarm detection count. This alarm indicates that a specific output has been activated a set number of times, potentially signaling that a connected actuator or contactor is nearing its operational lifespan or a process requires monitoring.
Common Causes
- Output ON times count reached the alarm detection count threshold configured for monitoring output activations.
Repair Steps & Checklist
Click steps to track your progress.
- 1
Set the corresponding bit of 'Number of output ON times value clear request' to 1 (Requested) to clear the accumulated number of output ON times.
Verified technical data. Last updated: March 2026
Related Faults
Source: Mitsubishi Electric MELSEC iQ-R I/O Module