i always reccomend changing bkup pow supply
batteries(usually gel cell). every 3-5 years.
however saying that the best test is have the customer go off hook on 20-30% of their sets and pull the plug and see if the battery
last as long as they need it to. how do the rest of you guys handle your customers back-up power?
m
p.s.better yet do it two days in a row to make sure the battery will recharge
also be aware that the amount of talk paths in use will correspond negatively with how long
it can keep the system up.

[This message has been edited by martin (edited September 17, 2004).]