Cypress Duprex

Supervised contacts and programming resistors:
One of the features of the Duprex is that it supports the use of supervised contacts. By setting
programming resistors on the Central unit, the status of contacts and end of line resistors on the
Remote unit can be monitored.
Two of the inputs support supervised contacts. The Alarm and Digital I/O #3 can operate in
supervised mode.
Supervised mode uses the programming resistors on the Central unit to determine what value of end
of line resistor it should sense on the Remote unit. If the value of the programming resistor and the
end of line resistor is equal, the output is not activated. If they are not equal, the output is activated.
End of line resistors from 1K (1000 ohms) to 20K (20,000 ohms) can be used. The resistor for the
end of line should match the value of its associated programming resistor.
C
R
Ground
Digital I/O
programming
resistor
Ground
Alarm
programming
resistor
Digital I/O #3 Alarm
Contact and end Contact and end
of line resistor of line resistor
©2005 Cypress Computer Systems,Inc. • www.cypressworld.com 11/21/05 Page 25