Operation Manual

Sensor test procedures
267
850-165186 / Rev.B
(4) = A second start flash: This signals that the second
digit of the channel number is next.
(5) = None to nine short flashes: The number of short
flashes signifies the second digit of the configured
channel number.
3 Using a multimeter, check the DC current between the
negative charging lug (A) and the water detector (B).
- With the initial sea water switch and a a fully charged
battery, the current should not exceed 150 µA.
- With a redesigned sea water switch (sacrificial bolt)
and a a fully charged battery, the current should not
exceed 67 µA.
- If you measure 0 µA, check the fuse on your
multimeter.
Testing on land
1 Connect the PI Service Hydrophone to the PI Operator
Unit.
2 Place the sensor on a level surface with its “domed top”
pointing towar ds the test hydrophone approximately five
meters away.
3 Use the Status display on the PI to monitor the sensor’s
signal strength.
- If the interference filter is on, the spectrum displayed
should be relatively flat (approximately 25 dB,
interference filter set at level 9) with a peak detected in
the configured channel.
4 Check that the bottom contact symbol on the PI is
“touching the bottom” when the detector wire is not pulled
out.
5 Pull out the detector wire, and check that the sensor
presentation changes.
Testing in water
1 Disconnect the PI Service hydrophone, and reconnect the
vessel’s normal hull mounted hydrophone.
2 Switch off the vessel’s echo sounders, sonars and other
hydroacoustical equipment to avoid interference.
3 Lower the sensor over the side of the vessel.
- Note that the weight of the sensor in water
(approximately 1.4 kg) may not provide sufficient
resistance to trigger the sensor’s bottom contact
function when the detector wire is pulled. Apply extra
weight if required.