Macurco GD2A Natural - LP -Methane Gas Detector
Flush mount Natural / Propane Gas detector.
12/24 Volt Ac or Dc operation.
The GD-2A is a low voltage (12-24 VAC or VDC) all electronic detector of combustible gases- that has been evaluated by UL for methane (natural) and propane (LP) gas.
The GD-2A is designed for connection to UL Listed alarm control panels (Fire orFire/Burglar type or Critical Process Management Equiptment) - although it may be usedalone - with UL Listed Class 2 limited energy power supplies.
The GD-2A has a SPDT Alarm relay - for connection to control panels or other devices.
InstallationAnd Specifications
Specification Sheet
The GD-2A uses a full wave bridge rectifier at its power input, so that it is independent of the polarity of the input power. It can operate on DC or AC voltages between 12 and 24 volts.
A switching regulator is used to efficiently match the wide input voltage range to the fixed, internal power system. As a result the power consumption is fairly constant at about 0.75 watts in normal operation, and 1.0 watts in alarm.
The GD-2A has an internal 2 minute time delay, that prevents alarms during the warm-up of the gas sensor. During the warmup period the green LED light blinks on and off. Once the delay is over, the continuous green light (ARMED) indicates normal operation.
The GD-2A has a supervisory circuit of critical functions. A trouble condition, due to failure of a non-reliable component, results in both lights switching on and off and the normally closed trouble relay opening. A power failure also causes the trouble relay to open. T
he red LED (ALARM) turns on at the same time the SPDT alarm relay activates, to indicate the alarm condition. The relays are reed type devices that are glass encapsulated, thus are ignition protected. In the configuration, as shipped from the factory, the GD-2A is self-restoring. When the air clears of gas, the red light turns off and the relay switches to its normal state. A jumper wire on the circuit board can be clipped to allow the unit to latch in upon alarm. Once latched in, power will need to be interrupted to un-latch the alarm condition.
The GD-2A does NOT detect carbon monoxide.
· CAN BE SELF-RESTORING OR LATCHING
· ELECTRONIC SENSORS: NO MAINTENANCE OR RECALIBRATION
· TEMPERATURE COMPENSATED
· SIMPLE INSTALLATION AND OPERATION
· FAIL SAFE SYSTEM: SUPERVISED SENSOR
· IGNITION PROTECTED DESIGN
SPECIFICATIONS
SIZE: 4 ½ X 5 X 1 ½ inches
SHIPPING WEIGHT: One pound
VOLTAGE: 12 to 24 VAC or VDC
CURRENT (non-alarm): 60 ma @ 12 VDC, 30 ma @ 24 VDC
CURRENT (in alarm): 83 ma @ 12 VDC, 42 ma @ 24 VDC
COLOR: White
SENSOR MAINTENANCE: Not required
ALARM RELAY RATING: 0.25 Amps, 100V, 3VA
TROUBLE RELAY: 0.50 Amps, 200V, 10 VA
OPERATING TEMPERATURE RANGE: 32° to 120° F
ALARM SET POINT: Per UL 1484 (25% LEL)
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