Allen-Bradley 23PFC, Hardware Service Manual

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10 Rockwell Automation Publication 23PFC-TG001A-EN-P - March 2018
Chapter 1 Before You Begin Testing, Maintenance or Repairs
General Safety Precautions Read the following precautions before you test components, perform
maintenance, or repair the device.
ATTENTION: Only qualified personnel familiar with DC drives, field controllers,
and associated machinery should plan or implement the installation, start-up
and subsequent maintenance of the system. Failure to comply can result in
personal injury and/or equipment damage.
ATTENTION: This device contains Electrostatic Discharge (ESD) sensitive parts
and assemblies. Static control precautions are required when you install, test,
service or repair assemblies. Component damage can result if ESD control
procedures are not followed. If you are not familiar with static control
procedures, reference A-B publication 8000-4.5.2, “Guarding Against
Electrostatic Damage” or any other applicable ESD protection handbook.
ATTENTION: Severe injury or death can result from electrical shock, burn, or
unintended actuation of controlled equipment. Hazardous voltages can exist
in the device enclosure even with the circuit breaker in the off position.
Recommended practice is to disconnect and lock out control equipment from
power sources. If it is necessary to work in the vicinity of energized equipment,
the safety-related work practices of NFPA 70E, Electrical Safety Requirements
for Employee Workplaces, must be followed. DO NOT work alone on energized
equipment.
ATTENTION: Potentially fatal voltages can result from improper usage of an
oscilloscope and other test equipment. The oscilloscope chassis can be at a
potentially fatal voltage if not properly grounded. If an oscilloscope is used to
measure high-voltage waveforms, use only a dual channel oscilloscope in the
differential mode with X 100 probes. It is recommended that you use the
oscilloscope in the A minus B Quasi-differential mode with the oscilloscope
chassis that is correctly grounded to an earth ground.
ATTENTION: Remove power before you make or break cable connections.
When you remove or insert a cable connector with power applied, an electrical
arc can occur. An electrical arc can cause personal injury or property damage
by:
• sending an erroneous signal to your system field devices, causing unintended
machine motion
• causing an explosion is caused in a hazardous environment
Electrical arcing causes excessive wear to contacts on both the module and its
mating connector. Worn contacts can create electrical resistance.
ATTENTION: HOT surfaces can cause severe burns. Do not touch the heat sink
surface during operation of the device. After you disconnect power, allow time
for cooling.