MV3DB Series DB Units
6. Preventive Maintenance
(07/06)
ALSPA MV3000e Dynamic Braking Units
Page 6-1
6. Preventive Maintenance
WARNING
•
Wait at least 5 minutes after isolating supplies and check that voltage between DC+
and DC- has reduced to a safe level before working on this equipment.
•
This equipment may be connected to more than one live circuit. Disconnect all
supplies before working on the equipment.
•
Surfaces on braking resistors can reach high temperatures and remain hot for
some time after power has been removed.
6.1
Tools and Equipment Required
Torque wrench, suitable size for power terminals, for range of torques as follows:
M6 (1/4 in) to M12 (1/2 in), range 8 - 45 Nm (70 - 400 lbf in)
Flat blade screwdriver, suitable for opening the power door (RH door).
Vacuum cleaner having soft (e.g. rubber) nozzle.
6.2 Maintenance
Schedules
Note:
It is suggested that these schedules be integrated with those for the drive unit.
6.2.1
Access to Equipment
1.
Switch off the drive and isolate it from the electrical supply. Comply with the Warning at
the top of this page.
2.
Gain access to the drive interior by opening the doors as shown in Section 4.3.2.
6.2.2 Monthly
Servicing
1.
Ensure all braking resistor ventilation louvres are unobstructed.
2.
Examine DB Unit connections to the DC link terminals DC+ and DC–, also to the braking
resistor terminal BR, for signs of overheating (discolouration and/or damaged
insulation).
6.2.3 Annual
Servicing
1.
Carry out the Monthly schedule as above.
2.
Use the vacuum cleaner to remove dust etc. from the braking resistor enclosure.
3.
Check all DB Unit and braking resistor terminations are secure, refer to Table 4-1 in
Section 4.3.1 for torque settings.
