SABs & Battery Packs

[AdrianUK]

We all know that the gel batteries in an alarm panel should be replaced at regular intervals but what about the battery packs in SABs?

I know that these are a different battery technology (usually NiCAD or NiMH) as opposed to the lead acid types used for panel backup and are usually soldered in but they must have a service life?

Does anybody routinely replace the module/entire bell box after a certain number of years?

On a slighty differnt note, I have an Elmdene 7422-EN SAB module on my desk, most of the connections are obvious, but two are not so:

H- Negative hold off
H+ Positive hold off
BAT- Flying negative lead from internal battery pack
FAULT ? internal self test failure, I guess. Does this switch to +ve or -ve?
REM TST ? Remote test ?
ENG Hold off - by-pass tamper when engineer on site so that cover can be removed without triggering siren
TR ? Tamper return to panel
TS ? Tamper source ? normally connected to H- but could be connected inline with H- of another SAB?
R- -ve trigger
ST- -ve trigger strobe.

Also, what is the purpose of the small wire loop to the left of the LED?

Thanks

 

[AdrianUK]

For the benefit of anyone searching the forum in the future.....

The consensus from other forums is:

i). Nobody routinely replaces a SAB module/battery pack after a set number of years. Most are left in service until they fail.

ii). Almost all engineers will test the SAB by dropping the hold-off voltage & allowing the unit to sound from its own battery - some will do this for the full 15/20mins others will do it for 5min or so - if the siren is still sounding at its initial rate after 5min they regard the battery as fine.

The 7422-EN module ....

TR is tamper return.
TS is tamper source.

The wire link connects -H to TS. Fine for a single siren install but needs to be cut for a twin siren install to allow the tampers to be connected in series.

Haven't worked out REM TST or FAULT ....... yet!