Isolation; Areas Of Control - Emerson Liebert iCOM Training And Service Manual

The path of a signal from beginning to the end - using the four block process.
T/H
INPUT
The temperature sensor senses a rise in temperature. The rise is transmitted to
the Central Processing Unit (CPU). The CPU looks into its memory for information
and instructions on what to do with the rise in temperature. The CPU then makes
the decision to call for cooling.

Isolation

We use the opto-isolator and the triac to isolate areas of control and voltage.
There are three areas of control and two voltage levels. Digital control comes from
the microprocessor at 5 VDC and the other voltage level is 24 VAC. One voltage
is used to turn on the triac and the other is used to operate the load device.
DIGITAL
Processor
3.3 VDC Signal
OPTO
3.3 VDC
Ground
ISOLATION
iCOM
Control Training and Service Manual
C P U
MICRO
MEMORY
CONTROL
Transformer
Power 24 VAC

Areas of Control

147
OUTPUT
LOAD
POWER
TRIAC
Transformer
Power 24 VAC
ISOLATION
Load
Device