ITT PumpSmart PS220, Руководство по конфигурации и эксплуатации

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PS220 Configuration & Operation Guide
85 PS220
M
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1. “ARROW RIGHT” To change
2. “ARROWS” to change value
3. “Save”
4. “ARROW DOWN”
E. Configure the SPT HI
1. “ARROW RIGHT” To change
2. “ARROWS” to change value
3. “Save”
4. “Next”
F. Configure the Hi INTRCPT
5. Exit the Wizard
Below is the example that is also shown in the Functions and Features to assist you.
Note:
This is only available for Single Pump Applications.
EXAMPLE – A pump configured for constant pressure draws from a tank. The level in the tank varies greatly,
and occasionally drops enough that the pump begins to cavitate. The Basic Pump Protection on the PS220
would limit the speed of the pump or shut it off. Using the Multivariable Control feature would allow for
pumping to continue, but at a reduced and allowable rate to prevent any harm to the pump, or the pumping
system.
A suction pressure transmitter would need to be added and wired into an unused Analog Input (AI2 in this
example). AI1 has already been configured for the primary control of the pump. The AI2 signal would then be
configured such that when the suction pressure is sufficient, the PumpSmart unit would run to its current ref-
erence. When the suction pressure dropped below a certain value it would start to change/offset the setpoint
based on the new scaling. In this case it would begin to lower the set point.
When configuring the Multivariable Control function, it is helpful to plot how you will want your set-point to
behave in relation to the seconds analog inputs signal.