The HMS Control ST panels are intended for control and protection of up to 4 surface installation centrifugal pumps (doble suction, overhung, etc.) and their analogs at the water supply systems, pressure boosting stations, and water lifting stations of the second or third lift. The panel provides operation of the pumping unit in manual, automatic and remote modes.
Regulation methods :
The panel maintains automatically the preset parameters of the water supply system by the following regulation methods:
Cascade regulation: a certain number of pumps with fixed rotation speed is switched on/off to maintain operation pressure in the system.;
Cascade / frequency regulation: a single frequency inverter regulates the rotation speed of one pump and depending on the required performance a certain number of additional pumps with fixed rotation speed is switched on /off.;
Frequency regulation: a frequency inverter on each pump allows the panel to maintain the system parameters by independent regulation of each pump rotation speed;
Main functions:
Coordinated operation of pumps to maintain the water supply system parameters, increase pumping units efficiency, operational lifetime and reliability of the pumping system in general;
Energy saving by 10-40% in comparison with systems regulated by the valves;
Automatic start of the standby pump in the event of the main pump failure;
Uniform total running time provided by periodical switching between main and standby pumps;
Automatic switching to reserve power supply (option). In the event of the voltage drop at the main power line the panel switches to a reserve power line (if provided) to continue operation in a preset mode;
Valves drives control (option). In automatic mode before switching on of appropriate pump the panel opens the suction valve and in a certain period of time opens the discharge valve;
User-configurable analog/digital input / output signal lines provides easy adaptation of the panel to a specific control system (see the options listed in the «Technical parameters» section).
Pump and motor protection features:
Pump shutdown at absence of water in the suction pipeline or a storage tank (dry running);
Thermal and maximum current protection of the electric motor;
Pump shutdown at low power supply voltage quality, phase break, distortion, wrong sequence;
Motor shutdown by the temperature cut-off switch (option);
Motor and pump parts temperature control (option, RT100/RTS sensor required);
Pump shutdown in case of external accident;
Emergency shutdown at an excessive value of adjustable parameter;
Pumping station shutdown at rapid pressure drop in the suction pipeline (e.g. pipeline breakthrough);
Limiting the number of starts per hour.
Interface
Items located on the control panel door
Selector of operation mode for each pump (Manual - 0 - Automatic);
Buttons of manual start/stop of electric motors;
Pump mode indicators: «Network», «In operation»;
Emergency indicator for each pump;
Voltmeter displaying values of supply voltage (option);
Ammeter displaying value of current consumed by each pump (option);
Controller display menu items:
Current value of the adjustable parameter and preset value;
