EQUIPMENT:
FIRE
CLASS
PRECEPT EN13
PUBLICATION:
FIRECLASS PREC EN13 INST
ISSUE No. & DATE:
2 22/07/2021
PAGE 11 of 32
9. Power Supplies
All panels produce dc power regulation directly on
the motherboard. A mains transformer is mounted
on the panel chassis to convert the incoming AC
mains voltage to a much lower AC voltage for DC
regulation.
For all panels, the output voltage is adjustable from
25V to 28.2V via a small trimmer potentiometer on
the PCB. As the output voltage is factory set
however, this should not be necessary.
9.1 Battery Charger
Each power supply provides a temperature-
compensated charging voltage for sealed-lead-acid
12V batteries connected in series. Charging voltage
range is 26.72V @ 50
o
C to 28.00V @ -5
o
C.
Battery sizes are:
•
2 off 12V, 3Ah for the 1.5A supply (2 & 4 zone
panels)
•
2 off 12V, 7Ah or 12 Ah for the 3A supply ( & 16
zone panels)
The health of the batteries, the battery connections
and fuse are checked by a battery monitor circuit
and automatic battery test facility once every 30
seconds. If the Battery is disconnected or the
Battery voltage falls below 15.7V or the Battery and
inter-connection resistance is greater than or equal
to 1Ω, the Batt/Charge fault LED is illuminated and
the Fault Output is operated. The circuitry also
protects against reversed connection of the
batteries.
9.2 Visual indications
The following visual indications are provided:
1) A green
‘Output - OK’
LED. This simply
denotes that power is being supplied to the
panel
2) A yellow
‘Batt/Charge Fault’
LED denoting any
one of the following conditions:
a) Battery or associated wiring disconnected
b) Battery fuse blown
c) Low Battery voltage (15.7V ±0.4V)
d) Battery and interconnection resistance is
equal to or higher than:
•
1
Ω
- 4-zone panels
•
1
Ω
- All repeaters
•
0.6Ω
- 8/16-zone panels
3) A yellow
‘Charger Fault’
LED (‘
Internal Fault
’
LED on the C1652 PSU board) indicating any
of the following:
a) A mains fault exists (see below)
b) Switching regulator or charger circuitry is
malfunctioning
c) Battery Fuse is blown
4) A yellow
‘Mains Fault’
LED. This indicates that
the mains voltage has failed or is less than the
required minimum for correct operation of the
power supply (80% of the rated voltage).
Note: Fault indications do not become active for a
minimum of 10 seconds after the fault has
occurred.
9.3 Battery Disconnect
1) The supply provides a battery disconnect
facility which disconnects the batteries when
the battery terminal voltage falls below 19.5V.
