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NOTE:
Under no circumstance should the technician take the STVI apart without
following proper ESD protection and handling procedures. Failure to do so, will
damage sensitive parts.
7.2.1.1 Power Input
Input voltage affects the whole unit, including the 48 Volts DC to the STVI from the PoE port,
and may or may not cause permanent damage if voltage is incorrect. These problems can often
be corrected by simply using a better source of input power. See unit front panel for input
voltage rating.
Some symptoms are as follows:
1.
Low voltage:
Erratic operation, no display, or a dim display.
2.
High voltage: Circuit breaker operation on MRCT unit, power supply failure.
a.
For MRCT, the internal power supply needs to be repaired or replaced, contact the
factory for further instructions.
7.2.1.2 Ethernet Cable
Basic troubleshooting of the Ethernet communication cable as follows,
1.
No power:
Check power source and line cord. If the MRCT powers up, but the STVI
display does light up, check the cable and cable connectors. Typical problem is usually a
broken conductor or cracked cable connector. Replace cable to see if this resolves issue.
2.
Erratic Manual Control
A.
Communication cable is not properly connected, thus cannot receive proper
commands.
B.
Internal problem with communications inside the MRCT
7.2.1.3 Ratio Errors
Ratio errors can be caused by a couple of things
1.
Ground issues
a.
The MRCT requires proper grounding either through the
power supply cord or through the chassis using the supplied grounding
strap. The unit uses this ground as a reference so for accurate testing
ensure that the MRCT is porerly grounded using the supplied chassis
ground strap.
b.
Tesing large power transformers and auto transformers. The MRCT has a
ground path inside the H1 ( Primary 1) lead. This is included in the
