I did dig into it and what should I say… I’ll switch to the native SNMP integration and hack down OIDs manually. No additional tool with fishy configs.
Here’s my solution: Get data from APC Smart + Network Management Card via SMTP - #22 by man55
I used the iReasoning MIB browser and looked for the appropriate values from the APC PowerNet MIB.
(don’t forget to add a .0 at the end)