Intrinsically Safe Barrier Relays Protect HazLoc Circuits

The aviation industry uses industrial controls and relays on aircraft and ground support equipment. Because maintenance, repair and operation (MRO) is done in hazardous areas that contain fuel, service equipment must be classified as Intrinsically Safe. In the event of a fault, IS relays protect the field circuit by preventing excess voltage and current from reaching the hazardous area.

Macromatic Intrinsically Safe Barrier Relays:

  • Ensure a safe workplace, protecting people and property.
  • Avoid the cost and bulk of explosion proof enclosures.
  • Make installation easy with their compact size and simple mounting.
  • Reduce costs using standard instrumentation cables.

Common Challenge

An aviation contractor that services jet fueling systems and portable fueling carts must use Intrinsically Safe Relays. Control circuits in the equipment use float switches to determine how much fuel is in the tank and control the fuel pumps.

Service technicians appreciate the extra working space afforded by compact relays. Easy access and bright LED indicators help to simplify service and testing. Having relays with the correct voltage with them can mean the difference between going home that night or waiting an extra day for a correct unit. 

Intrinsically Safe Barrier Relays used in aviation need these characteristics:

  • Provide safe control of loads with devices in all Divisions and Zones.
  • Compact enclosures with DIN-Rail or panel mounting.
  • Simple installation with color-coded, pluggable terminals.
  • Independent selection of operating modes/time delay on 4-channel models.

Our Solution

In hazardous locations, Macromatic Intrinsically Safe Barrier Relays protect and control loads without additional relays or contactors. IS control circuits operate at low-energy levels that cannot ignite potentially explosive atmospheres. These compact relays can be DIN-rail or panel mounted. Color coded, removable terminals make servicing easier. Contractors appreciate the universal voltage rating, which eliminates any concern about not having the correct unit available. Read More.

I was working on a refueling station when I realized it was a DC system. There was no supply house for hours and I had no idea how I was going to handle the Intrinsically Safe area. Fortunately, I realized that Macromatic IS Relays handle both AC and DC voltage. I hooked it up and it worked seamlessly. I was able to complete the job and get back home before the end of the weekend.

Service Technician, Aviation Service Contractor


Relay Solutions

Relays Provide Safe Operation and Extended Life for Aviation Applications


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