CSA C391-15:2020 pdf download.Testing of three-phase synchronous machines during refurbishment
4 Safety for inspections and tests
Prior to inspection or energizing of a machine, personnel safety shall be a primary concern. These machines can be extremely powerful and a common sense approach is essential.
Note: Safety issues are covered in detail by many organizations and documents, including CCOHS, CSA Group, IEEE,NEMA, NFPA, and UL.
The following installation and disassembly issues shall be considered:
a) Use only designed lifting lugs. All eye bolts shall be shouldered. Do not lift the machine by the shaft. Refer to the manufacturer's outline and instruction manual for lifting instructions. Check machine for a lifting nameplate.
b) The machine lifting lugs are designed for lifting the machine or part of the machine only, not the driven equipment.
c) Ensure the electrical grounding is proper.
d) Use qualified trained personnel to make the electrical connections.
e) Rotating parts (couplings, pulleys, fans and shaft extensions) should be protected by sturdy guards.
f) Be aware of the operating parameters of the machine (temperature, amperes, voltage, vibration,noise, etc.).
Note: Higher than necessary field current will lead to either exporting reactive power to the service shop system if acting as a motor, or excessive terminal voltage if acting as a generator. Either case will lead to potentially dangerous situations and should be avoided by adjusting field current to keep reactive power output near zero or terminal voltage at the rated level or less in the case of a generator.Properly secure shaft keys, coupling or pulleys, considering centrifugal forces.
h) Confirm that the applied voltage does not exceed the nameplate rated voltage plus 10%.
i) Confirm the connection of machine leads conform with the nameplate connection plate for the proper voltage.
j) Wear safety glasses and protection gear as appropriate.
k) After de-energizing the machine, ground all leads to dissipate residual charge. Ensure the machine has stopped rotating before grounding, as it will act as a generator while rotating, due to the magnet field decaying gradually, rather than immediately. Test for voltage before touching and conductors.
Note: If a machine failure is suspected, use extra caution in all areas and always be aware of the status of the power source.
5.1 General
Laboratory conditions and equipment are not required for these tests to be conducted. The tests may be conducted by the service centre using their normal production testing equipment. However, the instrumentation shall be of a quality and accuracy described in this Clause of the Standard. For these tests, instruments that will read voltage, current, power, resistance, temperature, and speed shall be used. For the low-voltage single phase test and current variation test, an analog type of ammeter or a recorder (i.e., chart recorder or digital oscilloscope) might be required to observe the actual variations in the line current.
Note: Suitable instruments are those that measure single as well as multiple parameters and those with data logging capability.CSA C391-15 pdf download.