SDG – Technologies

Liquid Resistance Starter

What is an LRS?

A Liquid Resistance Starter (LRS) – sometimes referred to as an electrolytic starter, in which the starting current of very large electrical motors is controlled by using in series with the motor-winding, a resistance consisting of an electrolytic bath through which current has to flow. The liquid acts as a resistor, limiting the starting current, like a large electric motor.

Why do you need a LRS?

A wound rotor (or slip ring) motor can provide unparalleled starting performance in applications where the driven machine has a high starting load and/or there is a need to start with the absolute minimum current draw. To prevent damage to electrical motors, gearboxes, pinion gears and girth gears an LRS is necessary to prevent such problems from arising.

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LRS & Safe Start Documents

Datasheet for Advanced LRS
Advanced LRS Protection Overview
Testing of an LRS on a grinding mill – Typical Results
Safer Starting – Engineering Background
LRS Maintenance Manual
Datasheet for Cooler
List of installations

Other Hardware Datasheets

Datasheet for Etherpad (232)
Datasheet for Etherpad (485/Epad3)
Datasheet for Buffer
Datasheet for BMSRTU
Datasheet for OPTO3
Datasheet for OPTO4
Datasheet of OPTO1