Honeywell MS-2 manual Input Circuits, IDC Connections

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 I3 smoke detectors which generate a maintenance signal when the 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 I3 smoke detectors, any 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.

Class B Initiating Device Circuits (supervised and power-limited)

4.7 KΩ, ½ watt resistor P/N:71252

manual pull stations

Note: Zones 3 & 4 on MS-4 only

Figure 2.4 IDC Connections