2-34
AFP-400 Installation
PN
50253
:
A2 03/12/96
Follow these guidelines when wiring the AC branch circuit current :
The control panel requires connection to a separate dedicated AC fire
alarm circuit, which must be labeled FIRE ALARM.
The AC power circuit must connect to the line side of the main power
feed of the protected premises.
No other equipment can be powered from the fire alarm circuit.
The AC power circuit wiring must run continuously, without any discon-
nect devices, from the power source to the fire alarm control panel.
Overcurrent protection for this circuit must comply with Article 760 of the
National Electrical Code as well as local codes.
Use #12 AWG wire with 600-volt insulation for this circuit.
Use the following table to determine the total amount of current, in AC
amps, that a 120V, 50/60 Hz service must be capable of supplying to the
system. Devices rated for 240 VAC operation will draw one half the current
listed in Table 2-1.
Power Supply Calculations
Device Type
No. of
Devices
Current
(amps)
Total
Current
AVPS-24
[ ]
X
1.00
=
AA-30
[ ]
X
1.00
=
AA-120
[ ]
X
1.85
=
MPS-400
[ ]
X
3.00
=
Remote Battery Charger
NR45-24
X
1.0
=
Sum column for AC Branch Current required
=
amps
Table 2-1 120 VAC Fire Alarm Circuit
The MPS-400 must be capable of powering all internal system devices (and
several external types of devices) continuously during non-fire alarm condi-
tions. Use calculation column 1 in Table 2-2 to determine the Non-Fire
Alarm Load on the MPS-400 regulator when applying primary power. The
MPS-400 must provide a finite amount of additional current during a fire
alarm condition. Use calculation column 2 in Table 2-2 to determine the
additional current needed during fire alarms. The requirements for non-fire
alarm and fire alarm current loads cannot exceed the capabilities of the
MPS-400 in either case.
The MPS-400 can provide the following:
a total of 3 amps at 24 VDC during Standby; and
6 amps at 24 VDC during alarm.
The Main Power Supply
(MPS-400)
AC Branch Circuit Current
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