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2. TEST OF LEAK
The digital unit is in monitoring mode. Simulate in several areas a leak, in order to check the correct
operation of the digital unit. The accuracy of the localization is ± 1 metre to the leak.
Caution:
A fault must be present for at least 30/40 seconds before being detected by the digital unit. In the
same manner, the digital unit passes again in Standby mode, 30 seconds after the physical
suppression of the fault.
Put a little water on the sense cable. Do not put the connector and the black sheath in water!
The red luminous witness ignites and a message of leak appears. If a relay is associated to this fault,
it rocks.
Once the leak has been dried, it takes a few moments, a message appears displaying the end of the
fault, the luminous witness becomes green, the relay rocks in to its initial position and the digital unit
passes into Standby mode.
3. TEST FOR CABLE BREAK
DISCONTINUITY TEST
There are three types of discontinuities:
1. Bus discontinuity
The bus discontinuity is a loss of communication with a sense cable.
It can occur when a cable is disconnected or cut.
The digital unit always indicates the first cable that is no longer responding.
Caution: When the end of a sense cable is disconnected, it is the next one that can no longer
respond and that will be declared as a bus discontinuity.
The preceding cables remain operational.
2. Cable discontinuity
Sense cables are composed of external wires for detection and internal wires for
communication.
When only the external wires are damaged, the digital unit reports a cable discontinuity.
In this case, the digital unit indicates the damaged cable but all the preceding and subsequent
cables remain operational.
3. End of circuit discontinuity
The end of circuit discontinuity indicates that the terminator plug is missing.
The position of the plug is calculated automatically at startup of the system when all the cables
are installed and there are no more faults.
It is therefore possible to have end of circuit discontinuities at the wrong addresses during the
installation and startup phases.
In this case, run a system test to view the number of sense cables recognized and find the first
cable that has not replied to the digital unit.
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