SilentKnight SK-4 Conventional FACP 2 & 4 Zone - Manual (Page 12)

12 SK-2 & SK-4 Series Manual — P/N 52604:B 9/14/2010
Product Description Controls and Indicators
Initiating Device Circuits - TB3
Alarm Zones 1 & 2 (SK-2 and SK-4)
Alarm Zones 3 & 4 (SK-4 only)
Power-limited circuitry
Operation: All zones Style B (Class B)
Normal Operating Voltage: Nominal 20 VDC, Maximum 27 VDC
Alarm Current: 15 mA minimum
Short Circuit Current: 40 mA maximum
Maximum Loop Resistance: 100 ohms
End-of-Line Resistor: 4.7K
, 1/2 watt (Part #71252)
Standby Current: 4 mA
Refer to the Silent Knight Device Compatibility Document for listed compatible devices
Notification Appliance Circuit(s) - TB2 1
One NAC on SK-2, two NACs on SK-4
Operation: Style Y (Class B)
Power-limited Circuitry
Normal Operating Voltage: Nominal 24 VDC, Maximum 27 VDC
Maximum Signaling Current: 2.5 amps total with standard transformer. 5.0 amps total (2.5 amp
maximum per NAC) with optional transformer on SK-4 only
Maximum Line Impedance: 1.5 volt drop end-of-line
End-of-Line Resistor: 4.7K
, 1/2 watt (Part #71252)
Refer to the Silent Knight Device Compatibility Document for compatible listed devices
Form-C Relays
Trouble Relay TB5 (fail-safe)
Alarm Relay TB6
Supervisory Relay TB7 (SK-4 only)
Relay Contact Ratings: 2 amps @ 30 VAC (resistive)
Resettable Special Application Power - TB1
Operating Voltage: Nominal 24 VDC
Maximum Available Current: 500 mA - appropriate for powering 4-wire smoke detectors
(see Footnote 1.)
Power-limited Circuitry
Refer to the Silent Knight Device Compatibility Document for compatible listed devices
Nonresettable Special Application Power - TB1 (SK-4 only)
Operating Voltage: Nominal 24 VDC
Maximum Available Current: 500 mA (see footnote 1 on page 12.)
Power-limited Circuitry
Refer to the Silent Knight Device Compatibility Document for compatible listed devices
1.3 Controls and Indicators
Front Panel Membrane Buttons
•
Acknowledge
• Alarm Silence
• Reset
1. Total current for resettable power and one Notification Appliance Circuit must not exceed
3.0 amps for the SK-2. Total current for nonresettable power, resettable power and two
Notification Appliance Circuits must not exceed 6.0 amps for the SK-4 (requires optional
second transformer).