ITT PumpSmart PS220, Руководство по конфигурации и эксплуатации

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PS220 Configuration & Operation Guide
143 PS220
Function & F
eatures
Dead Head
Dead Heading is a term used to define when a pump is running at “A Zero Flow Rate” AND producing pressure in
the discharge piping. When this occurs, the pump is also generating work in Horsepower. Depending on the HP
of the pump this pressure generated can be a large value. The HP generated for all centrifugal Pumps follow the
Affinity Laws. The Pressure generated will be directly proportional to the square of the running speed, and HP will
be to the cube of the speed.
This can be the result of:
1. A pump that is “undersized” that cannot generate enough pressure to move fluid to the end point in the
discharge.
2. A discharge valve that has been closed inadvertently or has failed in the closed position.
3. A blockage or Clog in the discharge line preventing any flow from exiting the discharge end of the piping.
When using the PumpSmart PS220’s PID Pressure or Smart THD Control Logic this can be completely avoided by
performing the “Dead Head Test”
This test will require the wired pressure sensor (Pressure PID)/gauge (SmartTDH) on this discharge end of the pip-
ing that is placed down-stream of a check valve and a discharge valve that will completely prevent any flow into
the piping system. That valve will need to be able to be completely closed with no path for any re-circulation back
to the suction. The suction line will also need to be completely open and flooded with all air vented out of the
pump. When all of these conditions are met, you will need to do the following.
NOTE: All Configuration should be completed prior to this step EXCEPT for pump protection.
1. Open the Suction Valve.
2. Vent all air out of the discharge side and what may be inside the pump.
3. Open the Discharge Valve 100%
4. On the PS220 Set Parameter 30.11 (Min Speed) to no less than 25% of the nameplate speed of the motor.
5. Enter the setpoint that you will be using that run the system.
6. Issue a start command. The PS220 will then run at a speed to maintain the setpoint for your system.
7. Slowly close the discharge valve until its 100% closed.
8. Document the speed the PS220 runs at when the valve is 100% closed.
9. Issue a STOP command.
10. Set Min Speed in 30.11 to at least 100 RPM above the value from Step 8.
11. Open the discharge valve 100%
If “Min Speed Sleep” has been configured using The Process Control Wizard. This system is now configured cor-
rectly so that it will never “Dead Head”
12. Finish any remaining Configuration as required.
To perform this Test on non-Pressure controlled and Speed Controlled pumping systems follow the following
procedure:
1. Open the Suction Valve.
2. Vent all air out of the discharge side and any that may be inside the pump.
3. Open the Discharge Valve 100%
4. On the PS220 Set Parameter 30.11 (Min Speed) to 25% of the nameplate speed of the motor.
5. Set the drive to run in local control using the LC/REM button.