User's Manual

Table Of Contents
Connecting Contact Alarms to a Unison System
7-48 InterReach Unison Installation, Operation, and Reference Manual
CONFIDENTIAL D-620003-0-20 Rev J
The micro controller sees a high or 5V for an open condition. The loop resistance
must be greater then 20K Ohm to guarantee the micro sees 3.5V or greater.
The micro controller sees low or 0V for a closed condition. The loop resistance
must be greater than 2K Ohm to guarantee the micro sees 1V or less.
You may have to determine a time on and off for the connection so that the alarm
is not intermittent.
Firmware has a five second hysteresis to ensure the micro does not capture inter-
mittent contact closures.
Table 7-12 Output Electrical Characteristics
I max is 5V/10K = 500uA. +/- uA due to R and V tolerances.
Vmax is 5V+5% from power supply spec.
Parameter Description Specification
I Max Continuous Load Current 550uA
V Max DC volts out 5 V + 5%
T on Max Max Turn-on Time 5 Seconds
T off Max Max Turn-Off Time 5 Seconds