Masibus LC5296-XP User Manual

Model: LC5296-XP-AT/LC5296-XP/LC5296-XP-I
Doc. Ref. no.:- m61D/om/101
Issue no. 17
User’s Manual Page 42 of 56
Control Parameter:-
Proportional BAND:
Proportional action is the action which the control output varies in proportion to the
deviation between the setting value and the processing temperature. If the
proportional band is narrowed, even if the output changes by a slight variation of the
processing temperature, better control results can be obtained as the offset
decreases. However, if when the proportional band is narrowed too much, even
slight disturbances may cause variation in the processing temperature, and control
action changes to ON/OFF action and the so called hunting phenomenon occurs.
Therefore, when the processing temperature comes to a balanced position near the
setting value and a constant temperature is maintained, the most suitable value is
selected by gradually narrowing the proportional band while observing the control
results.
Integral Time:
Integral action is used to eliminate offset. When the integral time is shortened, the
returning speed to the setting point is quickened. However, the cycle of oscillation is
also quickened and the control becomes unstable.
Derivative Time:
Derivative action is used to restore the change in the processing temperature
according to the rate of change. It reduces the amplitude of overshoot and
undershoots width. If the derivative time is shortened, restoring value becomes
small, and if the derivative time is made longer, an excessive returning phenomenon
may occur and the control system may be oscillated.
Manual Reset:
Virtually no process requires precisely 50% output on single output controls or 0%
output on two output controls. Because of this many older control designs
incorporated an adjustment called manual reset (also called offset on some
controls). This adjustment allows the user to redefine the output requirement at the
set point. A proportioning control without manual reset or Integral time (defined
above) will settle out somewhere within the proportioning band but likely not on the
set point.
Some controls use manual reset (as a digital user programmable value), this allows
the user to preprogram the approximate output requirement at the set point to allow
for quicker settling at set point when Automatic reset (Integral time) set to zero.
Range for the manual reset is -50.0% to +50.0% of proportional band.
Cycle Time:
The Cycle time for output is the time where the output is on for percentage of that
time and off for a percentage of that time, creating a portioning effect. The cycle time
is only used where PI, PD or PID control action is used. The shorter the cycle time,
the higher the proportionate resolution is, and better is the control.
For Relay output: Set to 10 to 300 seconds or more
For SSR output: Set to 1 to 60 seconds or more

Masibus LC5296-XP Specifications

General

Brand	Masibus
Model	LC5296-XP
Category	Controller
Language	English