TECO speecon 7200ma - PID Control Wiring; PID Wiring Diagram Details

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The above parameters are factory set for optimum results for most applications, and
generally do not need to be changed.
The PID Primary Delay Time is a parameter that adds a filter to the PID output to keep
it from changing too quickly. The higher the setting, the slower the PID output will change.
All of these parameters are interactive, and will need to be adjusted until the control
loop is properly tuned, i.e. stable with minimal steady-state error. A general procedure
for tuning these parameters is as follows:
1. Adjust Proportional Gain until continuous oscillations in the Controlled Variable
are at a minimum.
2. The addition of Integral Time will cause the steady-state error to approach zero.
The time should be adjusted so that this minimal error is attained as fast as possible,
without making the system oscillate.
3. If necessary, adjust derivative time to reduce overshoot during startup. The drive’s
acceleration and deceleration rate times can also be used for this purpose.
Output
Time
Before
After
If overshoot occurs, shorten the derivative
time (D) and lengthen the integral time (I).
Output
Time
Before
After
To ra
p
idl
y
stabilize the control conditions
even when overshootin
g
occurs, shorten the
inte
g
ral time
(
I
)
and len
g
then the derivative
time (D).
Output
Time
Before
After
If oscillation occurs with a lon
g
er c
y
cle
than the inte
g
ral time
(
I
)
settin
g
, it means
that the inte
g
ral o
p
eration is stron
g
. The
oscillation will be reduced as the inte
g
ral
time (I) is lengthened.
Output
Time
Before
After
If oscillation c
y
cle is short and a
pp
rox. the
same as the derivative time
(
D
)
settin
g
, it
means that the derivative o
p
eration is
stron
g
. The oscillation will be reduced as
the derivative time
(
D
)
is shortened. If even
settin
g
the derivative time
(
D
)
to 0.00
cannot reduce oscillation, then either
decrease the
p
ro
p
ortional
g
ain
(
P
)
or raise
the PID primary delay time constant.