Network UPS Tools (NUT) with CyberPower UPS input voltage sensor constantly dropping to 0v

Hi everyone,

I used to run an APC UPS with NUT with no issues.

Last week I swapped out the APC UPS for a CyberPower UPS (CPS CP1500EPFCLCD) connected via the same USB cable to my RPi which is running the latest HA.

I’m constantly seeing the Input Voltage sensor drop to 0v for varying amounts of time, usually just a few minutes, before the input voltage returns to normal.

The actual input voltage is constant, it’s not dropping at all, this is a false positive.

All other NUT UPS sensors are still reporting correctly while the input voltage drops to 0v.

Has anyone else come across this issue? :thinking:

Where might I start in trying to diagnose this issue? :thinking: