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1) LED ON. It blinks for about 2 minutes (warm up time) when the mains power is supplied. When ready, the
LED stays on without blinking.
2) BATTERY LED. It lights up (fixed) when no mains power is present and the control unit is supplied by a 12Vdc
battery. It blinks when the battery is flat.
Note: During the warm up time the control unit is not capable of detecting gas.
3)
OVER LOAD PROBES
LED. If this LED turns on, it means there is a short circuit or high current absorption
in the probes.
4)
OVER LOAD BATTERY
LED. If this Led turns on, it means the battery is not connected properly, or it has
an anomalous voltage absorption.
5) TEST BUTTON. Pressing and holding down this button, you can obtain a gas leakage simulation. In order
to perform this operation no failures or alarms should be present.
6) RESET BUTTON. This button is pressed to clear all memories, or to restore the control unit after a failure.
7) 1
st
Alarm LED. This LED will light up when the gas concentration level has reached 8% of LEL, or 120ppm
(ref. CO), and the 1
st
threshold relay contact is closed. The relay disenergizes when the 13% of LEL, or 200ppm
CO, threshold is exceeded.
8) 2
nd
Alarm LED. This LED will light up when the gas concentration level has reached 13% of LEL, or 200ppm
(ref. CO), and the 2
nd
threshold relay contact is closed. The buzzer will issue a low frequency sound. The relay
disenergizes when dropping below the 13% of LEL, or 200ppm CO, threshold.
9) MAIN ALARM LED. This LED will light up when the gas concentration level has reached 20% of LEL, or
300ppm (ref. CO), and the MAIN ALARM relay contact is closed. The buzzer will issue a high frequency sound.
10) FAULT LED. This LED blinks when one of the connected probes is faulty, if there is an interruption in the
cable connection, or if an error was made during wiring. When this LED is blinking, the device is no longer
capable of detecting. To reactivate the device, the damaged probe must be repaired or disabled using the
internal micro-switch (see chapter 6 paragraph A) and then the RESET button must be pressed.
11) EXPLOSIVE GAS LED. If this LED is turned on, the probe is set to detect explosive gas (Methane, LPG,
etc.).
12) DISPLAY backlight colours. The symbols are illustrated in the draw.
a) The symbol of the battery light on when the BX444-Mc is powered with an external battery.
The drawn battery indicates the state of load of the battery and when it blinks it means that the battery is low.
b) The number on the display indicates the concentration of gas detected.
The exchange of data of every connected probe is every about 4 seconds.
c) The letters ppm means when the connected probe detects Toxic gas.
The letters LEL means when the connected probe detects Explosive gas.
d) The symbol of the time means when the BX444-Mc is being the Warm up and displays the countdown.
13) TOXIC GAS LED. If this LED is turned on, the probe is set to detect toxic gas (Carbon Monoxide).
14) SENSORS LEDs (of the probes). These LEDs represent the connected probes and will light up in sequence.
Components and commands
Test
Reset
(5)
(6)
BX444-Mc
Main Alarm
2 Alarm
1 Alarm
Faul t
O N
Battery
Battery
Over Load
Sens ors
Over Load
(1)
(2)
(3)
(4)
(7)
(8)
(9)
(10)
100
ppm
1 2 3 4
SENSORS
ppm
LIE
(12) (11)
Switch 1
Intrinsic safety selection
Switch 2
Main alarm relay functioning mode
Switch 3
Maintaining of the memory of alarm,only when
you set the CO gas
Switch 4
Selecting OXYGEN mode
Power terminal block Sensors terminal block
S1 S2 S3 S4 1 2 3 4
Deleting or disabling the probes
monitored gas type selection
