Pittway NOTIFIER The SYSTEM 5000 Installation Manual page 47

Section 5.2: The MPS-24B Main Power Supply
Note: The MPS-24B has been designed to support single-cabinet row systems only.
This amounts to enough power for the CPU and up to three other modules as a maximum.
The MPS-24B Main Power Supply is a supply capable of powering the system continuously during standby and
alarm conditions. A total of 750 mA @ 24 VDC regulated is available for operating the system during Standby
conditions.
Figures 5-5 and 5-6 illustrate connections for primary and secondary power to the MPS-24B Main Power Supply,
as well as terminal and harness connections.
AC Power Requirements
The primary power requirement for the MPS-24B is 120 VAC, 50/60 Hz, 1.8 amps and the primary power
requirement for the MPS-24BE is 220/240 VAC, 50/60 Hz, 0.9 amps.
Connecting the Primary Power Source
With the breaker at the main power distribution panel turned off, remove the plastic insulating cover from Terminal
Block TB1 and connect the system primary power source. Connect the service ground to TB1-2. Ground the power
supply assembly to the cabinet with a Chassis Ground cable (71073) to TB1 Terminal 2. Connect the primary
Neutral line to TB1 Terminal 3 and the primary Hot line to TB1 Terminal 4. Do not route 120/240 VAC wiring in
the same conduit as other circuits. After completion of these connections reinstall the plastic insulating cover over
the terminal strip. Leave the main power breaker off until installation of the entire control panel is complete.
Connecting the Secondary Power Source
Secondary power (batteries) is required to support the system during loss of primary power. These batteries
reside in the control panel cabinet. Connect the Battery Positive Cable to TB3 Terminal 1 (+) and the Battery
Negative Cable to TB3 Terminal 2 (-). Do not connect the Battery Interconnect Cable at this time. This connection
will be made just after initial primary system power-up.
Earth Fault Detection
The MPS-24B automatically employs detection of earth faults in the system (unless Resistor R55 is removed).
Four-Wire Smoke Detector Power
Up to 200mA of current for 24 VDC four-wire smoke detectors can be drawn from TB2 Terminals 1 (+) and 2 (-
). Power is removed from these terminals during system reset (unless Jumper JP1 is removed). This regulated
four-wire smoke detector power is power-limited but must be supervised via a UL listed Power Supervision Relay.
The power supervision relay is energized by the four-wire power circuit and its contact must be connected in series
with an Initiating Device circuit.
(24 VDC)
Annunciator Power
The four-wire smoke detector output is the only source on the MPS-24B that can be used to power ACS
Annunciators. The power run to the annunciators is inherently supervised ( Loss of Communications error).
Note: The total current draw for all annunciator modules and four-wire detectors cannot exceed
200 mA either in standby or in alarm.
Notification Appliance power
Up to 2.0 amps of RMS regulated current for powering Notification appliances can be drawn from TB2 Terminals
3 (+) and 4 (-). Power is not removed from these terminals during system reset.
Note: This output is not suitable for powering annunciators!
System Harness Connections
Internal power for the system is provided via the Power Harness. Connect this harness from P2 on the MPS to
the CPU. Signaling between the CPU and the MPS is accomplished through connection of the Power Ribbon
(71085) to P3 on the MPS-24B.
(24 VDC)
(24 VDC)
(24 VDC)
S5000 15583 Rev. 6/10/96 P/N 15583:
47