ASTAT
SCR Module Replacement (Sizes P, Q, and R)
This procedure requires the following tools and materials:
•1/2" wrench, 3/16" Allen wrench, torque wrench
•Scotchbrite or equivalent abrasive
•Mild solvent to clean mounting surfaces
•Electrolube 2GX or equivalent thermal grease
1.Disconnect the control wiring harness for the SCRs to be replaced. If necessary, disconnect the wiring harness of the CTs.
2.Remove the bolt holding the busbar to the line side of the SCR Module.
3.Remove the bolt holding the CT, spacer, and load- side busbar to the SCR Module, as shown in Figure 15.
4.Remove the four screws holding the SCR Module to the mounting plate, as shown in Figure 16.
5.Lift out the SCR Module, as shown in Figure 17. Retain all parts and hardware for reassembly with the replacement Module.
6.Remove the MOV by disconnecting it at the spade connectors. Attach the MOV to the replacement SCR Module in the same manner.
7.Clean the heat sink surface of the replacement Module with a fine abrasive, such as Scotchbrite. Remove all particles from the heat sink surface and wipe the SCR mounting surface with a mild solvent. Apply a light coat of thermal grease, such as Electrolube 2GX to both the SCR and heat sink surfaces.
8.Place the new SCR Module in the proper position on the mounting surface. Move the Module back and forth several times to evenly distribute the grease on the plate.
9.Secure the SCR Module to the mounting plate with the screws removed earlier. Tighten the screws to 44
10.Reattach the busbars, CT, and spacer to the SCR Module with the bolts removed earlier. Tighten the bolts to 150
11.Attach the wiring harness of the new SCR Module to its mating piece. Attach the wiring harness of the CTs, if necessary.
Figure 15. Disconnecting the SCR load side..
Figure 16. Removing the SCR mounting screws.
Figure 17. Removing an SCR Module.
8 | Prices and data subject to change without notice. |
