Model gaZalarm The monitoring unit consists of :
- Power Supply Card : Size - 220 mm X 100 mm Supplies Power (9 V DC to 24 V DC) to complete system including gas detector assembly (Field Unit) with a current carrying capacity of one card is maximum up to 5 Amp. This can cater up to 10 cards in one rack. Multiple numbers of cards in multiple numbers of Racks in one panel can be provided if the numbers of channels are more than ten.
- Control card : Control card provides fixed voltage & current required to the field unit. It also accepts 4-20 mA signal from field unit. This signal is then processed by control card using instrumentation amplifier. The processed signal corresponding to the gas concentration available in the field is displayed by two or three digit 7 segments LED on control card display section. Two level alarms (latching/non latching type) are generated if the gas concentration is above preset limit. Fault alarm also is provided on the control card in case of sensor open/ short, cable from sensor is open/ short & under range/ over range conditions appear. The control card also delivers 4-20 mA.(repeater) output Signal for PLC / DCS.
- Facility Card : This card receives the alarm condition signal from control card. Depending upon the alarm conditions it activates the relays mounted on it & hoots the buzzer or siren or sends control signal to the pre-desired device. It also consists of alarm ACCEP, RESET & LAMP TEST conditions. The Push buttons are provided on the fascia plate to achieve the desired job.
- Mother Board : This board is provided on the back of 19” rack. The Mother Board PCB is provided with the copper tracks & Euro Connectors to hold all the cards like Control Card, Power Supply Card & Facility card. With the help of proper design reduces the back panel wiring of all cards