It is designed for continuous monitoring of three-phase electrical equipment (primarily 3-phase induction motors):

• mains voltage
• current values of phase / line currents
• power consumption
• voltages and currents in forward and reverse sequence
• insulation resistance to the housing
• differential earth leakage currents (zero sequence currents)
• temperature operating conditions

The unit is designed for wide application in engineering systems of buildings and structures (heating, ventilation, water supply, air conditioning), process control systems and industrial automation, control, metering and dispatching systems.
The unit significantly reduces the likelihood of failures of 3-phase electrical equipment, reduces the cost of operation, optimises power consumption and significantly improves the ease of use.
It has a complete set of protections implemented in UBZ-301.

Additionally, it provides protection against delayed start-up and rotor blocking, and monitors motor windings overheating using temperature sensors.

The presence of a second output control relay provides the possibility of organising additional operating modes:

• ‘star-delta’ switching
• switching with ‘delayed start’ (for example, cascade switching of motors)
• remote alarm relay