INTERNAL CONTROLS - Continued
Two zone Sigma | Four zone Sigma |
Normal switch positions | Normal switch positions |
TERMINAL FUNCTIONS
Smoke Detection Circuits
7.1One to six smoke detection circuits are provided and supply 28 Volts ( + 5%) for the operation of trigger devices, (smoke detectors or heat detectors). Terminals for the smoke detection circuits are labelled Z1+ and Z1- to Z6+ and Z6- for positive and negative connections respectively. It is important to observe the polarity of these connections for correct operation of the system.
7.2A 6K8 end of line resistor must be fitted to the last device on the smoke detection circuit for correct operation of the monitoring functions. Alternatively for greater system integrity a line continuity monitoring unit (LCMU) may be fitted.
Sounder Circuits
8.1Two sounder circuits outputs are provided and are labelled (S1
8.2Both outputs are monitored against open and short circuit faults in the field wiring. Any such faults are annunciated by the front panel system fault indicator immediately.
8.5The sounder circuit is normally fitted with a 20K end of line monitoring resistor.
Fault VFCO Contacts
9.1Volt free contacts are provided for remote signalling or plant shutdown on the occurrence of any fault condition.
Fire VFCO Contacts
10.1Volt free contacts are provided for remote signalling or plant shut down on the occurrence of any fire condition or evacuate condition.
10.2All contacts are rated at 30V DC 1 Amp maximum and should under no circumstances be used to switch greater voltages or currents (see annex 3).
Sigma K1000 Series 1, 2, 4 & 6 Zone Fire Control Panels Operation and Maintenance Manual
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