ITT PumpSmart PS220, Руководство по конфигурации и эксплуатации

Страница: 229 / 300

PS220 Configuration & Operation Guide
PS220 228
Functions &
Features
Stop Method
By default, the PumpSmart PS220 will “Ramp Stop” when commanded or when a fault occurs.
The parameters listed below can this to Coast if required and are independent of each other.
Parameter Name Value/Range Notes
21.03 STOP FUNCTION RAMP STOP [default]
COAST STOP
Selects how the motor will stop.
21.04
EMERG Stop Function RAMP STOP [default]
COAST STOP
Selects how the motor will stop with Fault or ESTOP.
Tuning
The PumpSmart PS220 utilizes onboard PID control when running in any Process Control Mode. The two primary con-
trolling functions are the Proportional Gain and the Integration time. The interaction of these properly configured settings
allow for the running speed of the pump to quickly stabilize when the pump is turned on, and when there are gradual or
rapid changes in the systems demand.
The Tuning parameter settings that are associated by default with the Control Mode selected while using the Process Con-
trol Tune Wizard may result in an unstable response from the PS220. The Proportional Gain and the Integration Time will
need to be “Fine Tuned” to alleviate this condition. Every pumping system is unique, and this is very common.
Following are a few “Rules of thumb” that can be followed as you adjust the parameters settings. You will need to access
the Tune Wizard to accomplish this.
These are in order of what to adjust first. After each adjustment you should wait a few minutes for the reaction to take
effect.
1. Rapid speed swings, or oscillations known as “Hunting” may be occurring. The audible “whining” of the drive as it
increases/decreases in speed by a large RPM value can be heard. The Integral time will need to be increase. This should be
done in increments of .5 seconds at a time.
2. When “Hunting” occurs as an “Overshoot” only, with the speed then coming down gradually, then the Proportional
gain will need to be lowered. This should be done in decrements of .2 to .5.
3. When “Hunting” occurs only an “Undershoot” then the Proportional Gain should be increased. This should be done in
increments of .2 to .5.
4. When there is minimal “Hunting” but still a lengthy time period before stable speed is achieved to maintain the process
set-point, the Integral Time should be decreased. This should be in decrements of .5 seconds at a time.
Notes
1. For level control application the Integral Time is very dependent on the size of the pump and the volumetric size of the
vessel pumping to/from. The default settings are preconfigured for large pumps with large vessels. This setting will need
to be lowered significantly if the pump is undersized.
2. The changing of the values of Proportional Gain and Integral Time may require several iterations to obtain the optimum
results.
3. “Start-up” conditions usually are quite different than actual process running conditions. Tuning adjustment are normally
required after initial commissioning.