Watlow CPC400 - Manual (Page 171)

CPC400 Series User’s Guide Chapter 6: Troubleshooting and Reconfiguring
Doc. 0600-2900-2000 Watlow Anafaze 157
Changing the Hardware Communications Protocol
To switch between EIA/TIA-232 and EIA/TIA-485, change
the jumpers as shown in Figure 6.5.
Figure 6.5 Jumper Configurations
You will need tweezers and a Phillips head screwdriver to
switch between EIA/TIA-232 and EIA/TIA-485:
1. Power down the unit.
2. Remove the controller’s metal casing. See Replacing
the Flash Memory Chip on page 154 for step-by-step
instructions.
3. Find jumpers JU2, JU3, JU4, and JU5 on the board.
4. Use tweezers to carefully grasp the jumpers and gen-
tly slide them off the pins.
5. Use tweezers to gently slide jumpers JU2, JU3, JU4
and JU5 onto the correct pins (see Figure 6.5).
6. If you are configuring the controller as the last device
on an EIA/TIA-485 network, move JU1 to the B posi-
tion.
7. Reassemble the controller.
Installing Scaling Resistors
Resistors are installed for all inputs on the CPC400. Inputs
with signal ranges between -10 and +60 mV use 0
Ω resis-
tors in the RC position only. All other input signals require
special input scaling resistors.
JU1
JU2
JU3
JU4
JU5
A B A B A B
Configured for
EIA/TIA-232
Configured for
EIA/TIA-485
Last controller in
system configured
for EIA/TIA-485