REED LOHE VI Series, Инструкция по эксплуатации, техническому обслуживанию и запасным частям

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BIM 1004/2005/05 Page 7 of 20 www.nord.com
TESTING AND FAULT ISOLATION
1. General
NOTE: NORD electric motors do not require periodic testing. However, if a motor is removed from its
installation, NORD recommends that the motor be checked according to the static and dynamic testing
provided below before it is reinstalled. Finding a condition that will require future repair before the motor
is reinstalled decreases the overall maintenance time.
This section provides general test information and functional checks for the types of motors covered by this manual.
All tests provided below may not apply to all motor types and models. Read and understand the tests and checks
before performing them on your motor. Understand how the test or check is to be performed and the pass/fail criteria.
Record and date all measurements taken. Retain the measurements in a file. Comparing current and previous
measurements is useful in tracking motor condition and brake wear, if the motor is equipped with a brake.
If the motor fails any of the test procedures provided below, use the fault isolation procedures to determine the motor
problem. Refer to the REPAIR section to determine if the failure is a repairable failure.
2. Testing
A. Static Testing
1. The motor can only be static tested if it is disconnected from the component it drives and securely
mounted on a fixture or mounting plate. These tests are usually conducted when a motor has been
removed for any reason other than failure
2. Turn the motor shaft slowly by hand. Feel and listen for evidence of a failed bearing, which is indicated
by a rough feel as the shaft rotates, and by noise.
3. Check for smooth rotation, with no evidence of binding or catching. If the shaft does not rotate
smoothly, or binds or catches, the bearings are worn or failing, lack lubrication, or are contaminated.
4. Check the motor shaft for side play by applying pressure at right angles to the shaft in several places
around the circumference. If the shaft moves perceptibly, the front bearing is worn.
5. If the motor shaft feels rough as it is turned or makes unusual noise, the motor bearings are failing, lack
lubrication, or are contaminated. Replace the motor bearings, or clean and re-lubricate the bearings, as
applicable. Refer to the REPAIR section.
6. If the bearing shaft shows play in the bearing, the bearing is worn or failing. Replace the motor bearings
according to the REPAIR section.
B. Dynamic Testing
1. Find the motor voltage and rated load current values as listed on the motor nameplate.
2. Using a volt-ohmmeter, verify that the motor power supply is in the correct range.
3. Run the motor with no load. As the motor is operating, listen for unusual motor noise and check for
excessive vibration. Vibration and motor noise are indications of bearing contamination, lack of
lubrication, damage, or failure.
4. Use an ammeter to measure the no-load current. Record the no-load current for comparison with
previous readings, and for reference during future testing.
5. If the motor passes the no-load test, operate the motor at rated load and check and record the current.
6. Check the motor operating temperature at rated load. If the motor operates at a higher than normal
temperature, the motor is failing.
7. If the motor has an integral brake, check the brake operating temperature. If the brake operates at a
higher than normal temperature, the brake is not releasing completely. Refer to the REPAIR section.