Allen-Bradley 23PFC, Руководство по обслуживанию оборудования, Страница: 67 / 150

Rockwell Automation Publication 23PFC-TG001A-EN-P - March 2018 67
Frame A Field Controller Part Replacement Procedures Chapter 3
SCR Module Replacement Remove the SCR Modules
1. Read the General Safety Precautions on page 10 .
2. Remove power from the device (see page 33 ).
3. Remove the protective covers (see page 36 ).
4. Remove the control EMI shield and control circuit board (see page 48 ).
5. Remove the pulse transformer and switching power supply circuit
boards (see page 50 ).
The device rating determines how the power bridge is configured and
the steps that are required to remove the SCR modules:
• See SCR Modules on 17 A and 60 A Field Controllers on page
67 .
• See SCR Modules on 120 A Field Controllers on page 68 .
SCR Modules on 17 A and 60 A Field Controllers
6. Remove the power traces circuit board. See Power Traces Circuit Board
Replacement on page 63 . The AC current transducers can remain on the
power traces board.
7. Remove the two screws and washers that secure each SCR module to the
heat sink and remove the SCR modules.
Continue with Install the SCR Modules on page 71 .
IMPORTANT The SCR modules must be replaced in pairs for each input phase in order
that the gating resistance of each pair of modules is the same.
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