Liquid resistor

They typically have electrodes made of welded steel plate (galvanised to reduce corrosion), suspended by insulated connections in a conductive chemical solution held in a tank - which may be open or enclosed.

A typical unit can be rated for continuous use, or for short periods when used for current limitation in protection systems.

The ohmic value of the resistor is calculated as a function of the permissible fault current and the system voltage to earth.

This salt solution is alkaline and electrode corrosion effects on galvanised steel tanks is manageable if re-galvanisation is possible.

A specialised technique is required to accurately calibrate an LNER electrolyte bulk resistance value and it is normally carried out by experienced power engineers and technicians.