Numeric Motor Protection Devices

Product Details:

UBZ-304 is designed for protection of induction motors with power of 2.5 to 315 kW (4HP to 500HP) in case of using the external standard current transformers with 5A output current. UBZ can be operated in networks both with insulated and dead grounded neutral. The unit is flush mount design version. UBZ provides continuous monitoring of mains voltage parameters, current values of the phase (line) currents of three-phase electrical equipment for 415V, 50Hz, and checking the resistance values of motor insulation.

UBZ-304 provides protection for AC electrical motors in case of:
- low quality network voltage (unacceptable power surges, phase failure, incorrect phase sequence and phase "coincidence", the imbalance of phase/line voltages, the reduction in the network frequency lower than the set one and (or) the increase of network frequency higher than the set value);
- mechanical overloads (symmetrical overload in phase/line currents);
- the threshold crossing of the negative-sequence current;
- imbalance of phase currents without overload associated with the insulation fault inside motor and/or the power cable (the comparison of current unbalance factor according to inverse sequence with voltage unbalance factor according to inverse sequence);
- the torque failure on the motor shaft ("dry running" for pumps) - protection based on the minimum starting and/or operating current;
- motor delayed start or rotor blocking; - extremely low isolation between the stator and the motor housing (pre-startup check);
- ground fault of the stator winding during operation
- earth leakage current protection;
- motor thermal overload;
- overheated windings (temperature of windings is determined using the motor built-in temperature transmitters or the temperature of the housing when using the external temperature probes, RTD type).

Further UBZ provides for electric motors control:
- using analog inputs "0-20 mA" and "0-10 V";
- using remote control channels (built-in RS-232 and RS-485 interfaces);
- by buttons on the front panel of UBZ.

Communication UBZ provides:
- parameters control and transmission by RS-485 interface using MODBUS Protocol,
- parameters control and transmission by RS-232 interface.

Availability of addtional programmable output relay allows for additional operation mode:

• Star-delta switching
• Delayed start power-on (for example, cascade motor starting)
• Remote signaling system relay (annunciation)

Documentation for this device

Additional Information:

• Port of Dispatch: New Delhi

Product Details:

Universal Protection Units For Asynchronous Induction Electric Motor

 

The unit is designed for continuous monitoring of three-phase electrical equipment parameters (primarily 3-phase asynchronous induction electro motors) mains voltage, phase/line RMS currents, wattage, positive and negative sequence voltages and currents, isolation resistance to frame, differential ground leak currents (zero sequence currents), temperature operation modes. The unit has been designed for wide range of applications in the buildings engineering systems (heating, ventilation, water supply, air-conditioning), Automatic Process Control Systems and industrial automation systems, systems of control, accounting and scheduling.

 

The unit allows reducing significantly the probability of 3-phase electrical equipment failure, reducing the operation cost, optimizing the energy consumption and enhance the using convenience.

 

It is equipped with complete set of protections implemented in UBZ-301 version. It additionally provides protection against long lasting start and rotor blockage, as well as motor winding overheating monitoring with use of temperature sensors.

 

Availability of another output relay allows for an additional operation mode:

 

• Star-delta switching
• Delayed start power-on (for example, cascade motor energizing)
• Remote signaling system relay

Documentation for this device

Additional Information:

• Port of Dispatch: New Delhi