ITT PumpSmart PS220, Руководство по конфигурации и эксплуатации

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PS220 Configuration & Operation Guide
PS220 152
Functions &
Features
Local Control (Speed Control)
When in LOCAL control mode the PS220 will only operate in the manual speed control mode using all functions on
the PS220 keypad. This includes controlling both the start/stop function and the reference speed setting. Local control
bypasses all PumpSmart PS220 control logic and functions except for ALL VFD PROTECTION which will remain intact.
Refer to Keypad use for operation on how to switch from LOCAL to REMOTE control.
Locking
The PS220 does not have the capability of locking or passcode/password protecting the configured settings.
It is always “open” by default and cannot be changed.
Minimum Flow Control
A pump is designed to maintain a minimum flow to ensure adequate cooling of the pump and to prevent the onset of
low flow recirculation. A pumps safe allowable minimum flow is normally based on hydraulic considerations such as
suction or discharge recirculation, minimum flow data and is available from the pump manufacturer. As a general rule,
at full speed, it is approximately 15-20% of the Best Efficiency Point Flow (BEP Flow). When pumping liquids with Vapor
Pressures that are close to “boiling at ambient temperature” a greater thermal minimum flow will need to be used. The
PumpSmart PS220 functionality can automatically adjust using the Advanced Smartflow feature.
Typical Performance Curve Depicting Minimum Flow