Housed in a convenient and attractive case these backup batteries will keep your phone system running in the event of a mains power failure.
Two cases are required per main equipment unit (KSU). Each case contains two 12 volt 7 amp/hour sealed lead acid (SLA) batteries for maintenance free operation.
Charged by the main equipment the battery set, from a full charge state, will keep the attached system and its handsets operational for a minimum of 1 hour for a fully loaded fully configured system.
The alternative : should the system not be battery backed, in the event of a mains failure, a number of PSTN trunks can be configured to failover to standard analog handsets or other (non mains powered) equipment to maintain a telephone service. However any calls in progress not on the failover trunks will be lost at the time of failure.
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