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Function Blocks
HOA Hand/Off/Auto Switch Function Block
176
HC900 Hybrid Control Designer Function Block Reference Guide
Revision 11
2/07
Example
H
Figure 43 shows a Function Block Diagram using an HOA function block in conjunction with a Device
Control (DC) block and an external HOA switch for pump control. The level signal input and Compare
(CMPR) function are used to determine pump On/Off demand.
O
O
O
O
O
O
O
O
A
O
H
A
O
H
To Pump
To Pump
External
Hand/Off/Auto
Switch
Device
Control
Status
Feedback
Level
Signal
Level
Setpoint
Figure 42
HOA function block example