Maintenance of Solid-state Devices
ATTENTION:
Risk of equipment damage exists.
Use of other than factory-recommended test equipment for solid state controls can result in damage to the control or test equipment or unintended actuation of the controlled equipment. Solid-state devices require little more than a periodic visual inspection. Discolored, charred, or burned components can indicate the need to replace the component or circuit board. Make necessary replacements only at the circuit board or plug-in component level. Inspect printed circuit boards to determine whether they are properly seated in the edge board connectors. Board locking tabs must also be in place. Solid-state devices must also be protected from contamination, and temperature control provisions must be maintained. Do not use solvents on printed circuit boards.
High-Voltage Testing
Do not perform high-voltage insulation resistance (IR) and dielectric withstanding voltage (DWV) tests to check solid-state control equipment. When measuring IR or DWV of electrical equipment such as transformers or motors, a solid-state device that is used for control or monitoring must be disconnected before performing the test. Even though no damage is readily apparent after an IR or DWV test, the solid-state devices are degraded and repeated application of high voltage can lead to failure.
Locking and Interlocking Devices
Check locking and interlocking devices for proper working condition and capability of performing their intended functions. Make any necessary replacements only with Allen-Bradley renewal parts or kits. Adjust or repair only in accordance with Allen-Bradley instructions.
Maintenance After a Fault Condition
An open short circuit protective device (such as a fuse or circuit breaker) in a properly coordinated motor branch circuit is an indication of a fault condition in excess of operating overload. Such conditions can damage control equipment. Before power is restored, the fault condition must be corrected and any necessary repairs or replacements must be made to restore the control equipment to good working order. See NEMA Standards Publication No. ICS-2, Part ICS2-302 for procedures. For replacements, use only parts and devices that Rockwell Automation recommends maintaining the integrity of the equipment. Make sure that the parts are properly matched to the model, series, and revision level of the equipment.
Final Check Out
After maintenance or repair of industrial controls, always test the control system for proper function under controlled conditions to avoid a control malfunction hazard. For additional information, see NEMA ICS 1.3, PREVENTIVE MAINTENANCE OF INDUSTRIAL CONTROL AND SYSTEMS EQUIPMENT, published by the National Electrical Manufacturers Association, and NFPA 70B, ELECTRICAL EQUIPMENT MAINTENANCE, published by the National Fire Protection Association.
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