Oldham Surveyor 4B, User Manual

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5 - Operating instructions 13
Chapter 5│ Operating instructions
Switching on
It is assumed that all the necessary connections have been made and that the
whole installation complies with the standards currently in force.
As soon as the SV 4B is supplied with power, it is ready to use and the
GREEN light-emitting diode lights up (rep 1, Figure 7).
Relay 1 is operated ("positive safety" position).
Switching off
The SV 4B is switched off by cutting off the power supply on an electrical
equipment cabinet.
Alarms
GAS alarm
The SV 4B has two adjustable GAS alarm thresholds but the second threshold
(AL 2) must be twice the first (AL 1).
Therefore, the red light-emitting diodes "AL1" and "AL2" (rep 3, Figure 7)
come on as soon as the alarm thresholds are exceeded (time delay of 7
seconds): LED flashing. The audio alarm (buzzer) is activated and the
corresponding relays are tripped.
Figure 7
item 4
item 1
item 2
item 3