Firstly, congratulations again on investing in safety equipment. Much like insurance, it's a 'cost' that doesn't always directly provide a return - but the day you need it, you will be happy you have it.
However, a PLB or EPIRB occasionally requires checking to ensure it isn't expired and still functioning as it should.
Expiry Dates
If you haven't already, check what the expiry date is on the unit's battery and record a reminder down somewhere to have it replaced. Maybe remind yourself a month or so before the unit expires so you can get ahead of it.
Self Testing
Most PLBs and EPIRBs have a self-test function that allows you to confirm the normal operation of the unit.
It's worth doing these as per the manufacturers' recommendation, as you don't want to find out something isn't working like it should be when you most need the unit to function!
You can find out more about battery replacement and self testing over here - https://beacons.org.nz/using-a-beacon/beacon-care/ - Maritime Safety have put together a great resource for you to find out more.