Control Panel for Pumps
The connection of the pumping unit to the electrical network should be carried out through a panel that performs the functions of protection and control of pumps.
The illustration shows a basic diagram of a control panel for two pumps installed in the circulation loop of the heating system, with a minimum set of functions for protection and automation of the pumping unit.
Protection
The pump control panel should provide the following basic protection:
- Dry run protection - the pump is switched off when the pressure in the suction pipe falls below the set value.
- Phase voltage unbalance protection - power supply to the pump is switched off in case of unacceptable phase voltage unbalance.
- Motor overload protection (thermal protection) - activated in case of shaft blockage and overload.
Control
Depending on the technological process conditions, the control panel may implement the following automation functions:
- Manual and automatic control depending on various conditions.
- Activation of a backup pump in case of failure of the working one.
- Automatic switching of operation from a backup to a working pump, thus ensuring even load and wear.
- Cascade pump activation based on a time schedule or deviation of a controlled parameter (such as flow rate or pressure) from a set value.
- Maintaining a constant flow rate, pressure or head behind the pump is achieved by installing a frequency controller.
- Blocking the pump start-up when the set frequency of activation is exceeded or depending on other conditions.
question : comment : feedback
108