SilentKnight SK-4 Conventional FACP 2 & 4 Zone - Manual (Page 20)

20 SK-2 & SK-4 Series Manual — P/N 52604:B 9/14/2010
Installation Input Circuits
2.3 Input Circuits
The SK-2 has two IDCs (Initiating Device Circuits) and the SK-4 has four IDCs. Each circuit is
compatible with System Sensor’s i
3 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 I 3 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 SK-2 and Zone 2 (IDC2) on the SK-4 can be programmed as
combination supervisory and waterflow zones. Refer to the Silent Knight Device Compatibility
Document for a list of compatible devices.
SK-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 (SK-4 only)” on page 25.
Figure 2.4 IDC Connections
Class B Initiating Device Circuits (supervised and power-limited)
4.7 K , ½ watt resistor P/N:71252
UL listed
compatible
2-wire smoke
detectors
manual pull stations
heat detectors Dummy load all
unused circuits - 4.7
K
, ½ watt resistor
(P/N: 71245)
Note: Zones 3 & 4 on
SK-4 only
ms-
4id
c.wmf
UL listed Power Supervision Relay
(refer to Device Compatibility Document for list of compatible relays)
Resettable 24 VDC
4-wire smoke
detector power
(500 mA maximum)
UL listed compatible 4-wire smoke detector