Pulsar M-920-S-001-1P, Service Manual, Page: 30 / 33

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The voltages shown above should be present at the unit and the junction box if
one is used.
The voltages come from the control unit to the transducer, the return signal is
current based and difficult to check in the field.
First remove the cable from the unit and check the voltages are there at the
terminals.
If the voltages are ok without the cables attached but change when the wires are
connected, then you have a wiring problem.
Connecting the wires incorrectly or shorting them out should not damage the
transducer.
Often the transducer extension cables are not the same colour as on the
transducer integral cables so the voltages need to be checked at the local junction
box to ensure they are there and connected correctly.
It is always preferable to commission the unit when there is a Sludge Blanket
present. If possible, establish where the blanket is before attempting to
commission the unit.
If after you have programmed your unit, the reading is not correct observe the
Echo Profile Display and ascertain if an Echo is present.
If an Echo is present but the reading is incorrect look for the following faults on
the Echo Profile Display.