Input Circuits - Fire-Lite MS-2 Instruction Manual

Installation

2.3 Input Circuits

The MS-2 has two IDCs (Initiating Device Circuits) and the MS-4 has four IDCs. Each circuit is
compatible with System Sensor's i
detector becomes dirty and a separate supervisory 'freeze' signal when ambient temperature falls
below the detector rating. The maximum loop resistance limit for each IDC is 100 ohms. The field
wiring for each zone is supervised for opens, shorts and ground faults (zero impedance to ground).
All conditions are visually and audibly annunciated.
Each circuit is configured for Style B (Class B) operation and will accept I
normally-open contact devices as well as conventional 2-wire or 4-wire, 24 VDC smoke detectors.
In addition, Zone 1 (IDC 1) on the MS-2 and Zone 2 (IDC2) on the MS-4 can be programmed as
combination supervisory and waterflow zones. Refer to the Fire•Lite Device Compatibility
Document for a list of compatible devices.
MS-4 Initiating Device Circuits can be converted to Style D (Class A) by installing the optional
Class A Converter module. Refer to "CAC-4 Class A Converter Module (MS-4 only)" on page 25.
(refer to Device Compatibility Document for list of compatible relays)
Resettable 24 VDC
4-wire smoke
detector power
(500 mA maximum)
20
smoke detectors which generate a maintenance signal when the
3
Class B Initiating Device Circuits (supervised and power-limited)
UL listed Power Supervision Relay
UL listed compatible 4-wire smoke detector
manual pull stations
heat detectors
Figure 2.4 IDC Connections
4.7 K, ½ watt resistor P/N:71252
MS-2 & MS-4 Series Manual — P/N 51512:G2 10/18/2011
Input Circuits
smoke detectors, any
3
UL listed
compatible
2-wire smoke
detectors
Dummy load all
unused circuits - 4.7
K, ½ watt resistor
(P/N: 71245)
Note: Zones 3 & 4 on
MS-4 only