Current Sensing Switches

Gas interlocking systems that utilise current sensing switches work by monitoring the flow of electricity to the extraction fan system. With the fan system not in use the switch detects the drop in amperage and does not allow the flow of gas to the appliances through the installed gas solenoid valves.

Current sensing switches are either able to monitor 1 individual fan, or 2 fans simultaneously. They can also be finely tuned, allowing the user to set high and low current ranges depending on the power demands of the fan system.


As an alternative to air pressure differential switches, current sensing systems rely on zero moving parts to function and are a great choice for a new installation. Merlin offer a number of options to choose from, all of which integrate seamlessly into their interlocking panels.