YOKOGAWA UT350, Инструкция по эксплуатации

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5-16
<Toc> <5. Parameters>
IM 05D01D02-41E
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Cycle Time
A cycle time can only be set if the type of control output is time proportional PID relay output
or time proportional voltage pulse output.
A cycle time refers to one period consisting of on-and off-state time lengths.
The ratio of the on-state time to the off-state time differs according to the value of the
control output.
The figure below shows on-to-off time ratios of the control output when the cycle time is set
to 10 seconds. Setting a shorter cycle time allows the controller to perform elaborate
control at short time intervals. This significantly reduces the on-and off-state times, how-
ever it shortens the service life of a relay.
On
Off
Cycle time
On
Off
Cycle time
Relay’s Behavior when Cycle Time = 10 sec.
For 20% of Control Output For 50% of Control Output For 80% of Control Output
On-state duration: 2 sec.
Off-state duration: 8 sec. On-state duration: 5 sec.
Off-state duration: 5 sec. On-state duration: 8 sec.
Off-state duration: 2 sec.
10 sec.
10 sec. 10 sec.
1st Edition : May 31,2000-00