Ametek SHZF2 SCR Series, Инструкция по эксплуатации и техническому обслуживанию

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Troubleshooting SHZF2/SHZF3 SCR Power Controller
24 Ametek HDR Power Systems Rev 2
d. Transport static sensitive components in static shielding bags or rails. A new printed circuit board
should be treated as a static sensitive device. A part completely installed on a board does not
make the part static-safe.
e. If possible, perform printed circuit board maintenance at a work station that has a conductive
covering which is grounded through a 1-megohm resistor. If a conductive table top is unavailable,
a clean steel or aluminum table top is an excellent substitute.
f. Keep plastic, vinyl, Styrofoam or other non-conductive materials away from printed circuit boards.
They are good static generators that do not give up their charge easily.
g. Return goods to Ametek HDR Power Systems in static-safe packaging. This will limit further
component damage from ESD.
h. CAUTION. Do not touch any printed circuit board unless you are wearing a ground wrist strap, as
circuit damage may occur. Grounding kits are also available commercially and can be purchased
through most electronic wholesalers.
7.4 Environmental Problems
Check to see that none of the following environmental problems exist.
Inadequate Cooling.
Allow at least 3 inches of air space (top or bottom direction) between the heat
sinks and any item or structure near the SHZF2/SHZF3 power modules. Heat sink fins should be free
of dust or dirt for proper heat transfer, and free of obstructions which could prevent proper airflow.
Contamination.
The unit should be periodically cleaned of all dust and dirt. However, certain kinds of
dust or particles are particularly conductive. A small accumulation of conductive material can cause
component failures from arc-over or complete shorts.
High Ambient Temperature.
Lack of a proper ambient-temperature check before installation, or an
increase in ambient temperature, can result in numerous problems. Check the ambient temperature
under existing conditions. If it is 122 ºF (50 ºC) or lower, ambient temperature should not be a
problem. If it is above 122 ºF (50 ºC), steps should be taken to provide more cooling, or the
SHZF2/SHZF3 should be moved to a cooler location, or call the Ametek HDR Power Systems
service
department.
Excessive Vibration.
A significant degree of pitched or unpitched vibration can cause numerous
problems. If vibration is isolated as a probable cause of improper operation, standard vibration-
isolation mounting techniques should be employed.
7.5 Input Power and Load Connections
Turn off the power to the SHZF2/SHZF3 and check all power connections, input and output, to make
sure they are mechanically secure and free of corrosion. Make the same checks at the power source
and load. Visually check insulation on input and load wiring for evidence of damage or overheating.