Secondary power supply – Potter PFC-7500 Series User Manual
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6.1
Battery Terminals 3 and 4
Connect the black battery lead to terminal 4 on the panel and then to the negative terminal of the battery. The negative
terminal connects to the enclosure ground internally through the PFC-7500 Series panel circuit board. Connect the red
battery lead to terminal 3 on the panel and then to the positive terminal of the battery. Observe polarity when connecting
the battery.
The PFC-7500 Series panels are capable of recharging two 7.7 Ah batteries (15.4 Amp/hours) within 24 hours.
Do not use battery backup with 24 VDC input: Do not connect batteries to the PFC-7500 Series panels when powering
the panels with 20 to 28.2 VDC voltage from a Fire Alarm Control Panel (FACP). The PFC-7500 Series panels use the
backup battery capability of the FACP for their standby requirements.
Use sealed lead-acid batteries only: Use only sealed
lead-acid rechargeable battery. Batteries supplied by Potter have been tested to ensure proper charging with Potter products.
DO NOT USE GEL CELL BATTERIES WITH THE PFC-7500 Series.
6.2
Earth Ground (GND)
Terminal 4 of the PFC-7500 Series panels must be connected to earth ground using 14 gauge or larger wire to provide
proper transient suppression. Potter recommends connecting to a metal cold water pipe or ground rod only. Do not
connect to electrical conduit or a telephone company ground.
6.3
Battery Replacement Period
Potter recommends replacing the battery every 3 to 5 years under normal use.
6.4
Discharge/Recharge
The battery charging circuit on the PFC-7500 Series panels float charge at 13.9 VDC at a maximum current of 1.2 Amps
using the Model WLT Transformer. The total current available is reduced by the combined auxiliary current draw from
terminals 6, 7, 15, 17, 19, and 21. The various battery voltage levels are listed below:
Battery Trouble: Below 11.9 VDC
Battery Restored: Above 12.6 VDC
6.5
Battery Supervision
The PFC-7500 Series panels load test the battery once every three minutes when AC power is present on terminal 1 and
2. The test lasts for five seconds. If, during the test, the battery voltage falls below 11.9 VDC a low battery is indicated.
The test is then repeated every two minutes until the battery charges above 12.6 VDC, the battery restored voltage.
If the low battery does not recharge and is replaced with a fully charged battery, the charged battery will not be detected
until the next two minute test is done.
If AC power fails during normal system operation, a low battery is indicated any time the battery voltage falls below 11.9 VDC.
Secondary Power Supply