Table of Contents
Advertisement
Test Points – Communication Terminals
The following table outlines the correct voltages for the test points on the communication terminal on the CA
or EC control board, the CB-485, or the CPB-10-2.
Communication Test Point
CA / EC Communication Terminal
RS-232 connected to ACU
GND
TD
RD
DCD
DTR
CTS
CB-485
At all ACUs
GND
GRN+
WHT-
BRN+
WHT-
TD
RD
Important
When a CB-485 is used, the Communication terminal block on the ACU main circuit board is in-active.
Measure only the CB-485 Communication terminal.
CPB-10-2
At all ACUs
GND
R
T
TD
RD
When a CPB-10-2 is used, the Communication terminal block on the ACU main circuit board is in-active.
Important
Measure only the CPB-10-2 Communication terminal.
Keyscan Technical Guide (PC109x - 04.12)
Table 16 – Communication Voltage Test Points
Voltage
(-) 9 VDC
(-) 10 VDC
n/a
n/a
3.5 VDC
1.5 VDC
3.5 VDC
1.5 VDC
(-) 7 VDC
(-) 7 VDC
12.8 VDC
12.8 VDC
(-) 11 VDC
(-) 10 VDC
Instructions/Notes
Connect Voltmeter COM to GND on ACU Communication
terminal block or green on data cable.
TD is an ACU generated voltage
RD is a PC generated voltage
Used for modems only
Connect Voltmeter COM to GND on ACU Communication
terminal block or green on data cable.
Remove jumper to plug in ribbon.
.
TD is an ACU generated voltage
RD is a PC generated voltage
Connect Voltmeter COM to GND on ACU Communication
terminal block or green on data cable.
Remove jumper to plug in ribbon.
.
TD is an ACU generated voltage
RD is a PC generated voltage
113
Advertisement
Table of Contents
