Yokogawa EJA118 - Manual (Page 51)

IM 1C22H1-01E 8-4
8. MAINTENANCE
8.4.2 Replacing the CPU Assembly
This subsection describes the procedure for replacing
the CPU assembly. (See Figure 8.4.2)
᭿ Removing the CPU Assembly
1) Remove the cover. If an integral indicator is
mounted, refer to Subsection 8.4.1 and remove the
indicator.
2) Turn the zero-adjustment screw to the position
(where the screw head slot is horizontal) shown in
Figure 8.4.2.
3) Disconnect the output terminal cable (cable with
brown connector at the end). When doing this,
lightly press the side of the CPU assembly connec-
tor and pull the cable connector to disengage.
4) Use a socket driver (width across flats, 5.5mm) to
loosen the two bosses.
5) Carefully pull the CPU assembly straight forward
to remove it.
6) Disconnect the flat cable (cable with black connec-
tor at the end) that connects the CPU assembly and
the capsule.
NOTE
Be careful not to apply excessive force to the
CPU assembly when removing it.
᭿
Mounting the CPU Assembly
1) Connect the flat cable (with black connector)
between the CPU assembly and the capsule.
2) Connect the output terminal cable (with brown
connector).
NOTE
Make certain that the cables are free of pinching
between the case and the CPU assembly edge.
3) Align and engage the zero-adjustment screw pin
with the groove on the bracket on the CPU
assembly. Then insert the CPU board assembly
straight onto the post in the amplifier case.
4) Tighten the two bosses. If the transmitter is
equipped with an integral indicator, refer to
Subsection 8.4.1 to mount the indicator.
NOTE
Confirm that the zero-adjustment screw pin is
placed properly in the groove on the bracket
prior to tightening the two bosses. If it is not, the
zero-adjustment mechanism will be damaged.
5) Replace the cover.