BI619954
Edition 03.2009
Maintenance
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Vacuum again
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If required, clean using dry cloths
6.13
Checking the main and auxiliary contacts of the contactors, transfer switch and the busbar connections in the DCC
Visual checks must be carried-out at regular intervals to check wearing parts associated with electromechanical switching devices and identify the effects of ageing at busbar connections. Carry-out the following for contactor K1, K2: •
Remove the arc quenching chamber at contactor K1,K2
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Check the main contactor contacts for erosion; when required, replace the main contacts (for instructions, refer to instruction manual for contactors)
•
Re-attach the arc quenching chamber
•
Check the auxiliary contacts for visible traces of erosion, when required, replace
Carry-out the following for transfer switch Q1.1, Q1.2, Q1.3 and motor module Q1: •
Check the main contacts of the switch modules for erosion, when required replace the switch modules (instructions on how to do this, refer to the chapter 7)
•
Check the auxiliary contacts on motor module for visible traces of erosion, when required, replace
Visually check the complete power section; in doing so, place give special emphasis on the following points: •
Are the cables damaged, is the insulation cracked or is there evidence of abrasion on the cables?
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Are components visibly damaged (phase modules, crowbar thyristor module, transducers)?
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Are the components and current-carrying parts discolored?
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Can white, crystalline traces be seen (these signify that the cooling system has leaks)?
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Are all of the cable lugs OK (none of the leads split, not discolored)?
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Is the busbar OK (visual check: Straight; no discoloring; no bubbling; not de-laminated)?
If there is evidence of problems or defects then they must be resolved.
Siemens Ltd. A5E01511750J/ 4M-2601-1645240 AC
Shovel 295HD/ HR DCC Operation & Maintenance Manual
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