Unit installation

Troubleshooting and Maintenance
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5.4.2 Test Cable
With every FS Trawl Monitoring system a 50’ test cable is supplied
for testing the system without requiring the 3
rd
wire trawl cable.
This provides a quick and simple way of verifying whether
problems are due to the trawl cable or winch slip-rings.
NOTE: The initial system performance values that are
measured on the test cable during the installation and
commissioning of the system provide a base for later
comparison.
5.4.3 Power Supply Meter Readings
The 3
rd
wire trawl cable voltage and ampere meters are useful for
monitoring the trawl unit power requirements. For the most benefit
these meters are mounted on the front panel of the PWR/TTM unit
next to the trawl voltage selection switch for continuous
monitoring.
When the system is first installed or when the trawl cable is
replaced the trawl cable voltage selection switch should be set to
200 VDC and current values should be recorded when the unit is
running in normal operating mode (i.e., with range and scan speed
set to values normally used during fishing) or set to the Factory
Default Setting.
Typical “Current Meter” values will typically vary from 190 mA to
350 mA depending on the type of sonar head connected to the 3
rd
wire. To facilitate monitoring of this information these values
should be recorded on the test report charts provided at the end of
this manual.
Any changes in the recorded meter values during normal operation
may indicate a potential problem even if the unit continues to
operate properly. Common cases are:
1. Current Meter Jitters:
This is commonly due to dirty, wet or worn winch slip-rings that
cause current spikes on the trawl cable when the winch is rotating.