Phonetics 5100 Home Security System User Manual


 
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Chapter 4: Inputs
CHAPTER 4
INPUTS
ISACC comes with 16 user definable inputs that can sense the following: temperature, analog
voltage, analog current, dry contact and pulse count.
HOW THE INPUTS WORK
ISACC reads the value of each input by measuring the voltage across the input terminal and
common. ISACC can read the voltage between 0 Volts and 5 Volts, in increments of .00489
Volts. The inputs are configured by positioning the shunts at location P12 on the ISACC
circuit board. (P12 is located under the acrylic safety panel directly above the input terminal
block. Refer to Appendix B for a diagram of the ISACC board layout.) P12 has 16 sets of
pins, one set for each input. See diagram of P12 below:
P12
TEMP
4-20mA
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
The input configuration pins at P12
When the shunts are positioned for a specific type of sensor, ISACC uses a different circuit to
measure the appropriate reading for that sensor. The three configurations are single ended 4-
20mA; thermistor/digital/pulse; and 0-5V. To configure an input channel, you must first