Watlow EZ-ZONE PM Integrated Controller - Manual (Page 151)

Watlow EZ-ZONE ® PM Integrated Controller • 148 • Chapter 10 Applications
Example 1: Single Loop Control
Requirements:
One input is required and at least one output adjusts the controlled part of the process.
Overview:
Controls one process value to a user entered Closed Loop Set Point based on an control algorithm.
Control loop 1 will control Analog Input 1 to Closed Loop Set Point 1.
Example 2: Sensor Backup
Requirements:
Two analog inputs and the enhanced software option are required and at least one output adjusts the controlled
part of the process.
Overview:
The Sensor Backup feature controls a process based on a primary sensor on Analog Input 1. If this sensor fails,
then the process is controlled based on the secondary sensor on Analog Input 2.
When function is set for Sensor Backup, the PV Function output equals Source A if sensor of Analog Input 1 read-
ing is valid or Source B if sensor reading is invalid. Control loop 1 will control the valid Analog Input sensor to
Closed Loop Set Point 1.
Control Loop 1
Single Loop Control
Closed Loop
Set P
oint
1
Heat
Algorithm
Cool
Algorithm
Analog Input 1 Source A Heat Power
Cool Power
Heat
Cool
0 to 100%
0 to 100%
Output n
Output n
Chapter 10: Applications
Sensor Backup
Closed Loop
Set P
oint
1
Function
Filt
er
Source A
Source A
Source B
Heat Power
Cool Power
0 to 100%
0 to 100%
Output
Heat
Cool
Output n
Output n
Analog Input 1
Analog Input 2
Control Loop 1
PV Function