Auto Switch (DOL/SEMI) – Gold Lotus Electronics

Model : DOL

Model : SEMI

Model : DOL-DS

Auto Switch (WTF/WDS) protects three phase electric motor against single phasing, reverse phasing and unbalanced supply voltage condition. It can be used for any HP rated motor. Trip time delay is provided to avoid mis-tripping of the motor.

90% of total burn of the motors are mainly due to over loading caused by unbalanced voltage & phase failure condition. These faults are undetected or detected too late by conventional bimetallic relays. These faults are can be correctly detected by negative sequence of voltage.

Technical Details
Voltage Sensing SPP	It gives protections at sensing points only. It sense negative sequence component of voltage and protects the motor against phase failure, unbalanced supply and reverse phase sequence of voltage.
Single Phasing	If any one phase is removed, the unit will trip the motor.
Reverse Phasing	When Phase sequence is reversed, motor rotate in reverse direction. This condition is not desirable to run the motor, so the unit will trip the motor.
Unbalanced Supply	If voltage un balanced is higher than 45V +/- 5V, it trips the motor.

Technical Specification
System Voltage	415V+/-20%,3O, 50Hz.
Output Contact Rating	1C/O potential free, 1 A at 415 V
Trip Time Delay	4 to 7 Seconds
Indication	Normal and Delay
Dimension	120x135x80mm.
Weight	480gms.(approx.)
Color	Dark Gray
Application	Agriculture motor starter.
Connection	Connector is provided.

Salient Features

Applicable to any HP motor.
Protect motor from negative sequence voltage.
Auto start on healthy supply.
Engineering grade plastic enclosure.

Protect motor from phase failure.
WTF is suitable for DOL and FASD starter.
WDS is suitable for SASD motor starter.
On time delay provide protection to pump from extra pressure