GDS C1, Instruction Manual

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3.1.2 OPTIONAL DISCRETE RELAY PCB # 10-0195
An optional Discrete Relay PCB , shown in Figure 3.4, adds eight 5 amp (resistive) form
C relays per sixteen channel alarm group (2 PCB’s required when utilizing more than 8
channels). Each PCB may be configured via rotary switch S1 to function for ALARM 1,
ALARM 2 or ALARM 3/FAULT for channels 1-8 or 9-16. A 1-minute time delay after
power is provided to inhibit relay actuation until the system has had time stabilize.
Alarm groups, or zones, may be created by connecting adjacent channels together using
JP4 as shown. This creates a wire
OR function with selected channels, causing any alarm
included within the zone to actuate ALL zone relays. Failsafe operation of 10-0195
discrete relays may be programmed in the system menu as described in section 2.3.2.
Many C1 applications utilize the common alarm relays (see section 3.0) and do not
require discrete relays for each of the 48 alarm events (16 A1’s, 16 A2’s & 16 A3’s). If
discrete relays are needed for all 48 alarms, then six PCB’s are required.
5 VDC power to the discrete relay option PCB’s is normally supplied from the C1
Controller via the slender I
2
C cables connected to J2 and J3. However, I
2
C cables are
limited in ability to carry this power further than a few feet without a significant voltage
drop. Some C1 applications with relays for all 48 alarms may require up to 6 boards.
TB2 allows a heavier 5VDC power cable to be connected from terminals on the back of
the C1front panel assembly, bypassing the I
2
C cable. A 20AWG pair connected to only
one of the several TB2’s is sufficient when these boards are in close proximity to each
other.
All relays are rated at 5 Amp for 28 VDC and 250 ~VAC RESISTIVE loads.
IMPORTANT: Appropriate diode (DC loads) or MOV (AC loads) snubber devices
must be installed with inductive loads to prevent RFI noise spikes. Relay wiring
should be kept separate from low level signal wiring.
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