5. SYSTEM PARAMETERS
PI: tranducer type
Allows the User to select the PI feedback signal Transducer type.
0: = [default] if the feedback signal is less than the PI setpoint the PI controller will
increase motor speed to correct this
1: = if the feedback signal is less than the PI setpoint the PI controller will reduce motor
speed to correct this
It is very important that the transducer type is correctly selected. If you are unsure that it
should be either 0 or 1 you can determine the actual type as follows:
Disable the PI function (P2200 = 0). Increase the motor frequency while measuring the
feedback signal. If the feedback signal increases with an increase in motor frequency the
transducer type should be 0.
If the signal decreases with an increase in motor frequency the transducer type should be
set to 1.
CO: PI scaled feedback signal
CO: PI error
Displays the PI error (difference) signal between the setpoint and feedback signals in
PI: proportional gain
Allows the User to set the proportional gain of the PI controller.
The PI controller on MM420 is implemented using the standard model:
Best results are usually obtained if both P and I terms are enabled. If the system is liable
to sudden step changes in feedback signal, the P term should usually be set to a small
value (L 0.5) with a faster I term for optimum performance.
If the P term is set to 0 the I term acts on the square of the error signal.
PI: integral time
Allows the User to set the PI controller integral time constant.
Refer to P2280 above for detail.
MICROMASTER 420 Operating Instructions
♦ ♦ ♦ ♦ P0003 User
♦ ♦ ♦ ♦ P0004 Setting
♦ ♦ ♦ ♦ Changeable
♦ ♦ ♦ ♦ Status