Keyscan CA250B, Technical Instructions

Page: 84 / 140

Keyscan Inc. – Technical Guide (PC109x - 04.15) 84
Control Board Voltage Test Points
The following table lists correct voltages for the control board’s test points. Be sure to review the notes
opposite the appropriate voltage test points to comply with proper measuring techniques.
Voltmeter Connections
 Voltmeter set to VDC
 V-Ω (ohms) to test points
 Com to ground lug in metal enclosure
Table 16 – Control Board Test Points - Voltages
Board Test Point Voltage Instructions/Notes
Reader Terminal
D1 WHT (+) 5 VDC White data 1 – if reader connected
D0 GRN (+) 5 VDC Green data 0 – if reader connected
PWR RED (+) 12VDC Red DC out
TP1
(+) 13.5 VDC Reader power
TP2
(+) 13.5 VDC ACU power
TP3
(+) 13.5 VDC ACU power after circuit protector
TP4
(+) 5 VDC
TP5
(+) 3.3 VDC
Input Points
Input points with open circuit (+) 5 VDC
Input points shorted to common
return 0 VDC