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to proceed:
Test Procedure: Adjust the target (displayed) speed as expected during normal operation, including
testing inhibit and jog transitions if applicable.
Tuning Method:
Step 1 - Connect control to loaded motor with application's anticipated load for realistic tuning
Step 2 - Perform test procedure
Step 3 - If control performs adequately, stop tuning and record settings
Step 4 - If control is too sluggish or takes too long to reach the target speed, then try increasing
I Gain slightly (add 250). Perform the test procedure again. Continue increasing I Gain
until motor starts to slightly oscillate or become unstable. At this point, decrease the I Gain
by 250.
Step 5 - If control is too aggressive or is causing the motor to oscillate or become unstable, then
try decreasing I Gain slightly (subtract 250). Perform the test procedure again. Continue
decreasing I Gain until motor starts to stabilize and regulate more accurately.
Step 6 - Once I is set, adjust P Gain and perform test procedure. In this control, additional P Gain
may or may not improve response or stability. Experimentation will be required.
Accel and decel settings have a small impact on PI tuning as well. Specifically, when accel and decel
settings are extremely fast, they can cause the control loop to perform more sluggishly. Another thing
to keep in mind is that PI tuning also affects accel and decel times. For instance, a sluggishly tuned
PI control loop may take longer than the programmed accel and decel times to reach the target;
whereas, an aggressively tuned PI control loop will reach the target faster.
Master (Rate and Time) and Follower (Ratio) Modes Explained
The MDP controls have two basic modes of operation, master and follower. In the Master modes, the
controls are capable of operating independently; whereas, in the Follower Mode, the control requires
a signal from a master to operate. The Follower Mode is used in applications which require the MDP
to closely follow a master process. For example, if a factory has ten conveyors which must be
synchronized over long periods of time, an industrial engineer could use one MDP as a master control
for the first conveyor and nine MDPs as slaves or followers which would receive their speed commands
from the first conveyor's master control or pickup.
In Master Rate Mode, the MDP controls the rate of the motor by tracking the motor's pickup pulses which
are applied to signal input 1 (S1). In this mode, the display indicates in rate units such as Gallons-per-
minute, feet-per-second, and RPM.
In Master Time Mode, the MDP controls the process time by tracking the motor's pickup pulses which
are applied to signal input 1 (S1). In this mode, the display indicates in time units such as HH:MM or
MM:SS, where HH is hours, MM is minutes, and SS is seconds. This mode is most-commonly used
in time-sensitive processes such as conveyor ovens and plating applications.
In Follower Mode, the MDP tracks the number of pulses which are applied to the master signal input
(S2). From these pulses, it calculates the rate of the master process. This rate is then multiplied by
the percentage which is displayed on the user interface. The display is in 0.1% of master units. For
example, 675 = 67.5 percent of master speed. A master running at 1350 RPM, would cause the follower
to run its motor at 67.5% * 1350 RPM or 911.25 RPM. Typical follower applications include
synchronized rotation, synchronized conveyors, and some web-material processes.
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