MMD Equipment 400S-6B1 - Manual (Page 45)

5. Periodic Inspection/Maintenance
5-6
H000049
5.5.2 Change engine oil filter
[At 250 hours for the first change and every 500 hours thereafter]
<Procedure>
① When installing a new oil filter“1”, spread oil over the
packing“2”, and then screw it in. When the packing
touches the sealing surface, further tighten the filter
by approximately two-thirds turn with a filter wrench.
② After the oil filter“1”is assembled, check if there are
any oil leaks during operation. (See 5.4)
5.5.3 Check Insulation resistance
[Every 250 hours]
When the generator has not been operated for a long time or moisture has entered inside the
machine, be sure to measure the insulation resistance. If resistance is lower than 1MΩ, it could
cause an electrical leakage or fire. Dry the generator with compressed air until the resistance exceeds
1MΩprior to operating.
Since the generator insulation may drop when moisture, oil vapor, and dust are stuck, always keep
the machine clean.
<Procedure> <Megger tester required>
① Remove the load side plate from the output terminal
board.
② Remove the cable between the terminal “N”and terminal
“Ground” which are connected on the back of the output
terminal plate.
③ Remove the AVR connector inside the generator control
panel.
④ Switch ON the three-phase breaker, measure each
insulation resistance between the terminals L1,L2,L3
terminal and bonnet.
⑤ Insulation resistance when measured with a 500 V megger
tester must be above 1 MΩ.
⑥ After finishing the measurement of insulation resistance,
re-connect the plate between the terminal “N” and
terminal “Ground”.
After making sure that the insulation resistance of the
generator is higher than 1 MΩ, be sure to re-connect the
cable between the terminal “N” and terminal “Ground”
just as it was originally connected.
If it is left disconnected, the grounding becomes imperfect
so that it could cause electric shock
.
2
AVR
Connector
A080064
A080063
Bonnet
1