Nidec 22765-01, Руководство пользователя

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Page 35
resistance values level off. Monitor winding temperatures. Raise
winding temperature gradually at a rate of 10° to 20° F (5° to 10° C)
per hour up to 200° F (93° C). Measure insulation resistance at 1-hour
intervals. Typically, the insulation resistance will slowly drop while the
temperature is coming up and then gradually increase and level out.
Bearing Lubrication
Shielded or Sealed Ball Bearings: Shielded or sealed ball bearings are
factory packed with lubricants and generally can be operated several
years without requiring replenishment or change of the grease. If
repacking the grease is necessary, disassemble the machine, clean the
bearings, and repack the bearings about half full using a high quality
ball bearing grease, which must be capable of lubricating satisfactorily
over a temperature range of the lowest ambient temperature to
250 ° F (121 ° C).
Regreasable Ball or Roller Bearings: In applications where
regreasable bearings are used, grease fill fittings and relief valves
are incorporated into the bearing housing. Lubricate the bearings in
accordance with the lubricating instructions attached to the generator.
Sleeve Bearings: Lubricate the bearings in accordance with the
lubricating instructions attached to the generator and the bearing
lubrication instructions, which are provided in the manual package as
supplementary material.
Rectifier Tests
If a failure of a rectifier is suspected, remove the exciter cover. Remove
the nut and washer holding the rectifier in the heat sink, and remove
the diode lead wire. Lift the rectifier from the heat sink (see Figure 20
for an overview). Test the entire rectifier with an ohmmeter or test lamp
as follows:
NOTE: For specific lubrication instructions,
always refer to the bearing lubrication
sheet that came with your manual or the
lube plate on the generator.
Figure 20 Example Rectifier (Form May Vary)
Negative
Positive
Positive