The GDA 490 is designed to control 1-8 GDA 290 sensors for applications where chiller/refrigerant plant is using PROPANE as the refrigerant gas. The control unit derives the 24 VDC required for the sensors from the mains i/p and activates a local 24 VDC o/p on alarm to drive a sounder/flasher AVR-20. The sounder flasher can be muted from the front panel. The alarm also activates a DPCO relay; the contacts may be used to shut down and pump down the system. The alarm is indicated on the front panel by LED’s.
DESIGNED, MANUFACTURED and SUPPORTED by GAS DETECTION AUSTRALIA.