User's Manual

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When installing the A4 power mesh board, lower it vertically, placing its tab into the A1 board slot first, align the connector
and press in place.
A5 Diode Board Removal
After removing the cover, remove the A5 Diode board by first removing the two cover screws (Pozidriv) that hold
heatsinks to the A1 board, then lift vertically to remove the A5 Diode board from the connector.
When installing the A5 Diode board, lower it into the mating connector on the A1 board, then install a screw between each
heatsink and Al board.
A3 Front Panel Board Removal
Remove the A3 front panel board by first removing the entire front panel assembly. You do not need to remove the top
cover. Follow this procedure:
a.
Remove the top plastic insert by prying up with a flat-blade screwdriver.
b.
Remove the four front panel assembly mounting screws (Phillips 6-32) two on the top and two on the bottom.
c.
Gently pull the front panel assembly away from the unit as far as permitted by the connecting cables.
d.
Note the locations of the four power-wire connections to the power switch and then unplug the quick-connect plugs.
e.
Unplug the W1 ribbon cable from connector A2J3 on the A2 control board.
f.
Remove the A3 board from the front panel assembly by removing the six mounting screws (Pozidriv, M4x.7)
Install the A3 Board by reversing the steps above. Connect the power switch wires in the exact locations from which they
were removed. See A1 Main Board Removal.
A1 Main Board Removal
Removing the A1 main board requires removing all the vertical boards except the A3 front panel board, and 17 A1 board
mounting screws, four standoffs, and two bus-bar mounting screws. Component-access cutouts in the bottom inside cover
allow unsoldering most A1 board components for repair without removing the A1 board.
Proceed as follows:
To remove the A1 board, proceed as follows:
a.
Remove the A2, A4, and A5 boards according to the above instructions.
b.
Remove the AC power cord from the cooling fan and the four AC Input Power wires.
AC Input Wire Terminal Destination
from color designator location
L6 (chassis) white P left rear
RFI filter white/gray N behind A1K1
Circuit breaker white/brown/gray L behind A1K1
L6 (chassis) white A1K1 front armature
c. Remove the following mounting screws:
2 (1 each) from the output bus bars
7 from the A1 board
4 from transformer AlT2
4 from transformer AlT3
2 from relay AlK1
4 inside-cover mounting posts 5/16 hex