Protection device for three-phase electric motors UZ1-MX

Voltage protection devices are designed for protective shutdown of electrical equipment, in particular, electric motors, refrigeration units, in the event of an emergency in both single-phase (220 V 50 Hz) and three-phase (220/380 V 50 Hz) electrical networks with a neutral wire.

The following emergencies are monitored:

• open circuit of the supply voltage phases;
• network voltage out of permissible limits;
• voltage imbalance between phases;
• adhesion of the phases of the supply voltage;
• violation of the phase sequence;
• overheating of electrical equipment;
• temperature sensor malfunction.

The device has input (X1-6) and output contacts (X7-11).
Input Contacts:

• X1-3 (ABC) - contacts for connecting phase voltages A, B, C;
• X4 (N) - neutral (device ground);
• X5 (F) - starter control contact;
• X6 (T) - temperature sensor connection contact.

Output contacts:

• X7 - X11 - relay contacts;
• P1-P4 - regulators for tuning.

The devices can monitor the voltage of a single-phase network (УКП1), a three-phase network (УЗ1), and also control the temperature of the motor winding (УЗ1-М1).
To control the voltage, the user sets the zone of the permissible network voltage Umin and Umax, the response time in case of an emergency (time of the network analysis) Tav, the temperature of the thermal protection operation T overheating (only for UZ1-M1).
Protection devices constantly analyze the supply network, in case of an increase in the mains voltage, more than Umax or a decrease in voltage, less than Umin, an emergency analysis of the network occurs (for UZ1, the amplitude imbalance of the phases Uper is also analyzed), while the LEDs indicate the cause of the failure. After the expiration of the Tav time, an emergency disconnection of the load from the network occurs, the red LED turns on, signaling the occurrence of an alarm. If the trouble disappears, the output is switched on again after the Tcl time.

Characteristics

* - the type of relay means 2 operation options:
1/1 - one relay controls the starter; the second is configured to turn on the emergency siren when the starter sticks;
2 - two relays duplicate each other and are configured to control the starter.
Umax - voltage, when exceeded, the relay is triggered;
Umin - minimum holding voltage of the relay;
Uper - the maximum allowable phase imbalance voltage;
Tcr - device response time;
Tvkl - time of switching on the load after restoring parameters;
t overheating - the maximum permissible object temperature.