Alarm Relay Connection; 4-20Ma Signal Connection; Installation - Macurco CD-12H Mode D'emploi

3.5 Alarm Relay Connection

The external alarm connections (A and B) are available at the Alarm modular connector. There is no polarity for these connections. To
install the wiring for the alarm contacts, disconnect the connector from the header on the detector. Strip the insulation off each wire back
approximately 1/4 in. (6.5 mm), insert the bare wire into the terminal and tighten the screw clamp. Ensure that the wire cannot easily be
pulled from the connector. When the wires are connected seat the modular connector into the header ensuring that the latch engages.

3.6 4-20mA Signal Connection

The positive and negative 4-20mA signal connections (+ and -) are available at the 4-20mA modular connector, a 2-position connector.
To install the wiring for the 4-20 mA contacts, disconnect the connector from the header on the detector. Strip the insulation off each wire
back approximately 1/4 in. (6.5 mm), insert the bare wire into the terminal and tighten the screw clamp. Ensure that the wire cannot easily
be pulled from the connector. When the wires are connected seat the modular connector into the header ensuring that the latch engages.
Note: The 4-20mA current loop outputs may be used with the Macurco DVP-120 control panel or other systems. The 4-20mA signal
connections to detectors should be size AWG18 (minimum) for short runs. Refer to the table for recommended wire gauges. Do not
bundle detector 4-20mA signal connections with AC power cables to prevent electrical interference. If AC power connections must be
bundled with the detector 4-20mA signal cables, the signal connections should be made with a twisted pair of the appropriate gauge,
with an overall foil and braid shield. All shields should be terminated at the DVP-120 end of the cable only. A ground stud is provided
near the bottom left corner of the DVP-120 panel.

3.7 Installation

1. The CD-12"x" mounts on a 4" square (or 4x4) electrical box supplied by the contractor. Do not mount the CD-12"x" inside
another box, unless it has good air flow through it.
2. Connect the CD-12"x' to the control cables with terminal plugs. When making connections, make sure the power is de-
energized.
3. There are two terminals for Power: 100-240VAC (50 – 60 HZ)
4. There are two terminals for the dry alarm relay contacts, again with no polarity preference. The alarm relay can switch up to
0.5 A 120 V, or 60 VA. The alarm relay is activated if gas reaches or exceeds the alarm settings. See section
OPERATION of these User Instructions for details on relay settings.
5. The alarm relay can be configured to normally open (default) (N.O.) or normally closed (N.C.) and will activate if the gas
concentration exceeds alarm set point. It will deactivate once the gas concentration drops below the alarm set point. Note that
the "disable" setting will cause the alarm relay not to engage at all.
6. The dry contact, SPDT fan relay has three terminals. The common (COM.), normally open (N.O.) and the normally closed
(N.C.) contact. The fan relay can switch up to 5.0 A up to 240 VAC. See section
for details on relay settings.
7. The Fan Relay can be configured for latching or non-latching (default) when activated (when the gas concentration exceeds
fan relay setpoint). Once latched in, power will need to be interrupted or the "TEST" button pressed to un-latch the relay
condition.
8. The Fan Relay will engage if the fan setting Carbon Dioxide concentration is exceeded for longer than the Fan Relay Delay
time. Unless it is configured for latching, the fan relay will disengage once both conditions have been met:
Carbon Dioxide concentration has dropped below fan setting
•
Fan Relay Runtime has been exceeded
•
Note that the "disable" fan setting will cause the fan relay to not engage. The fan relay will engage in trouble fault condition (if
the Trouble Fan Setting Option is set to "ON") and will disengage once trouble fault condition is cleared.
9. The Current Loop is 4 mA in clean air and 4-20 mA for 0-5000 ppm CO
3.9 OPERATION
2
7
3.9
of these User Instructions