UPS 300, UPS 301, UPS 500, UPS 600, UPS 750 and UPS 900 Uninterruptible Power Supplies Caterpillar

Attach a "Do Not Operate" warning tag or a similar warning tag to the key switch or to the controls before the system is serviced. Attach a "Do Not Operate" warning tag or a similar warning tag to the key switch or to the controls before the system is repaired. These warning tags are available from your Caterpillar dealer. Attach the warning tags to the system and to each operator control station.

Illustration 1	g00104545

Do not allow unauthorized personnel on the system, or around the system when the system is being serviced.

Speeds, temperatures, and load are the best indicators of performance. Rely on instrumentation. Record all readings. Compare these readings with previous readings in order to detect developing abnormalities.

• Wear a hard hat, protective glasses, and other protective equipment, as required.

• Do not wear loose clothing or jewelry that can snag on controls or on other parts of the system.

• Ensure that all protective guards and all covers are secured in place on the system.

• Never put maintenance fluids into glass containers. Glass containers can break.

• Use all cleaning solutions with care.

• Report all necessary repairs.

Unless other instructions are provided, perform the maintenance under the following conditions:

• The system is stopped and the system is disconnected from power. Ensure that the system cannot be powered or ensure that power cannot be applied to the system.

• Do not attempt any repairs that are not understood. Use the proper tools. Replace any equipment that is damaged or repair the equipment.

• Remove all tools, electrical cords, and any other loose items from the system before starting the system.

Safety Precautions

Read this manual thoroughly. Pay special attention to the sections that apply to you before working with this system. Retain this section for use by installing personnel.

While the doors are closed, only normal safety precautions are necessary under typical operation. The area around the system should be kept free from puddles of water, excess moisture, or debris.

Special safety precautions are required for procedures that involve the handling, the installation, and the maintenance of the system. Observe all safety precautions in this manual before the performance of all maintenance procedures and during the performance of all maintenance procedures.

This equipment contains several circuits that are energized with high voltage. Use only test equipment that is designated for troubleshooting, including the appropriate oscilloscope, if needed. Always check with an AC voltmeter and a DC voltmeter in order to ensure safety before making contact or using tools. Even when the power is turned Off, high voltages may exist at the capacitor banks.

ONLY qualified service personnel should perform maintenance on the UPS. When you are performing maintenance with any part of the equipment under power, service personnel and test equipment should be standing on rubber mats. The service personnel should wear insulating shoes for isolation from direct contact with the floor (earth ground).

Personnel should never work alone unless all power is removed from the equipment. A second person should be standing close in case an accident should occur.