Thermo Fisher Scientific
AutoPILOT PRO Flow Computer User Guide 11-1
Chapter 11
Maintenance
Warning
For hazardous area installations: In the event of a fault condition,
the AutoPILOT PRO flow computer cannot be serviced by the customer.
No repair to faulty assemblies should be attempted. Faulty assemblies must
be replaced with identical replacements. All repairs or part replacements
must be done by Thermo Fisher or its appointed repair agent. Contact
Thermo Fisher for instructions.
Follow the procedure below to replace the main board.
Warning
Ensure power is off and the area is non-hazardous before
performing this procedure.
Tip
The procedure for replacing the main board is the same for metal and
fiberglass enclosures.
1.
Open the enclosure door, and reference
a.
Remove the Honeywell EPROM from the main board. Do not
discard it, as you will need to install it on the replacement board.
b.
Remove the three screws holding the main board faceplate in place,
and remove the faceplate. Do not discard it.
c.
Disconnect all wiring from the terminal blocks. Noting each
connection will simplify the process when you are ready to connect
everything to the replacement board.
d.
There are two screws installed through the main board. One
connects the Q12 resistor to the chassis bracket, and the other
screws into a standoff on the mounting bracket. Remove these
screws.
e.
If you have the communication expansion option, there are two
additional screws installed through the main board that secure the
expansion board. Remove these screws.
f.
Loosen the two thumbscrews on the mounting bracket, and lift the
main board and bracket up to expose the back of the main board.
Replacing the
Main Board
