5) RESET BUTTON
A "RESET" button is provided to allow the user to cancel the events that occurred and are contained in the
memory by an intentional manual reset.
6) TEST BUTTON
Pressing the "TEST" button, it is possible to perform a functional test for the "pre-alarm" relay and the "general
alarm" relay, together with the warning lights and the acoustic alarm. Releasing the "TEST" button, its turns
off the lights and stops the acoustic alarm.
7) EXPLOSIVE GAS selection LED.
Turning on this LED indicates that the input has been configured to detect explosive gases.
WARNING! The flashing of the LED can also indicate the presence of under/over range entering input.
8) TOXIC GAS selection LED.
Turning on this LED indicates that the input has been set to detect toxic gases.
9) FAULT LED.
This LED lights up when a short circuit or open circuit occurs on the signal line.
WARNING! The blinking of both "Fault" LEDs indicates the occurrence of software or a power failure.
10) PRE-ALARM LED
This LED lights up when the gas concentration level reaches the second pre-alarm threshold (13% LEL for
explosive gases, 200 ppm for toxic gases).
This signal is "auto reset" type.
11) MAIN ALARM LED
This LED starts to blink when the gas concentration level reaches the main alarm threshold (20% LEL for
explosive gases, 300 ppm for toxic gases).
This signal is "latching", according to current performance standards.
12) DIP-SWITCH of the deadband suppression of the sensor 1 and 2
Setting these two switches ON or OFF, it is possible to enable or disable the suppression of the signaling of any
sub-range in the input signal in the corresponding input.
Instead, over ranges will always be reported.
Both conditions are indicated by the flashing of the "Explosive Gas" LED of the corresponding input. (7)
13) DIP-SWITCH OF POSITIVE SECURITY and RELAY MODE
Setting the first switch to ON or OFF, enables or disables the "positive safety" mode.
Setting the second switch to ON or OFF, switches to the main alarm mode CONTINUOUS or PULSE .
14) DIP-SWITCH OF SENSOR SELECTION and GAS TYPE SELECTION
Setting the first switch to ON or OFF enables or disables the corresponding input.
Setting the second switch to ON or OFF, switches to detecting gas from the explosive to the toxic.
WARNING! When a sensor is excluded, all memories will be restored.
The control units, in addition to the interfaces described above, is equipped with 3 output relays:
- FAULT RELAY: this "latching" relay switches when there is an error signal from the connected sensor (see
image below).
- PRE-ALARM RELAY: this "autoreset" relay switches when the detected gas concentration exceeds the second
pre-alarm threshold.
- MAIN ALARM RELAY: this "memory" relay switches when the detected gas concentration exceeds the main
alarm threshold.
WARNING!
All relay outputs of the control unit are voltage free.
The maximum range of such contacts is specified in the next chapters.
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