GE VersaMax PLC, User Manual

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10.9.3.1 Example
In the example, an Off-Delay Timer is used to turn off an output (%Q00001) whenever an
input (%I00001) turns on. The output is turned on again 0.3 seconds after the input goes
off.
CONST
+00003
OFDT
PV
%R00019
%I00001 %Q00001
CV
0.10
10.9.3.2 Operation of the Off-Delay Timer Function
ENABLE
Q
A B C D
E
F G H
A. ENABLE and Q both go high; timer is reset (CV = 0).
B. ENABLE goes low; timer starts accumulating time.
C. CV reaches PV; Q goes low, and timer stops accumulating time.
D. ENABLE goes high; timer is reset (CV = 0).
E. ENABLE goes low; timer starts accumulating time.
F. ENABLE goes high; timer is reset (CV = 0).
G. ENABLE goes low; timer begins accumulating time.
H. V reaches PV; Q goes low, and timer stops accumulating time.
10.9.3.3 Parameters of the Off-Delay Timer Function
Input/ Output
Choices
Description
address R
The function uses three consecutive words
(registers) of %R memory to store the following:
• Current value (CV) = word 1.
• Preset value (PV) = word 2.
• Control word = word 3.
Do not use this address with other instructions.
Careful: Overlapping references cause erratic
operation of the timer.
enable flow
When enable receives power flow, the timer’s
current value is incremented.
190 GFK-1503E VersaMax PLC User Manual
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