Ingersoll-Rand INTELLISYS SSR Series, Руководство по устранению неисправностей

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equipment, or other equipment that exhibits excessive electrical arcing during
operation (i.e. DC brush motors). The level of disturbance is generally known as
field strength. The electric field strength is measured in volts per meter (V/m). A
hand held 5 watt transmitter can generate 10 V/m electric field strength at a
distance of approximately 1 foot. To alleviate potential RFI and EMI disturbances,
ensure the equipment is properly grounded (see Grounding Problems) and
eliminate close range exposure to radiating devices.
ESD disturbances can be airborne as well as conducted into the equipment. The
ESD event occurs when an electrical charge is dissipated into the equipment.
This event is usually random and normally occurs with human interaction. A
human can carry an extremely high electrical charge (8 kV) by simply walking
across an insulated surface. Other sources include charged ungrounded
material that can come into contact with the equipment (example: The presence
of air flowing through a plastic pipe can cause an electrical charge to propagate
along the surface of the pipe and arc into a conductive surface). ESD safeguard
measures should be used when handling electronic circuit boards and
equipment. (See Field Service manual - Large Rotary (blue book) Section “B”
Sheet 12).
Lightning disturbances will generally occur more often in outdoor applications.
Obvious direct exposure to weather conditions will increase the chances of a
lightning strike. Direct lightning strikes can cause severe electrical damage to
controls, motors and wiring. The best precaution for this is to avoid open
exposure and ensure adequate facility protection such as lightning arrestors.
Power line transients and surges can cause a variety problems in the electrical
system . The transient or surge is defined as a random abnormal condition that
results in a distorted power signal. The distortion can usually be detected by
measuring the voltage of the incoming power signal. Power line transients
typically occur in fractions of seconds (less than 100 ms) and are hard to detect
with standard volt meters. An oscilloscope is usually required for measuring
transients. Power line surges occur at longer intervals (>100 ms) and can be
detected more easily with the use of a recording voltmeter (such as Fluke 87). If
the voltage level of the transient or surge is high enough, abnormal system
behavior can occur. These problems include:
Erratic control system behavior:
Fuse blowing
Control reset
Erratic Triac operation (output)
Control power transformer insulation breakdown:
Motor winding insulation damage
Solenoid coil winding insulation damage