Is the FOGRod intrinsically safe?

The FOGRod is a “simple apparatus” as described in NEC 504.4 and therefore does not need to be listed. It just needs to be installed in an intrinsically safe circuit. (See Division 1 Classification of the FOGRod). This is easily achieved with an off-the-shelf barrier.

Wastewater Level has tested two barriers and approved them:

– Pepperl & Fuchs: Z967
– R Stahl: 9002/77-220-146-001

Both of these are 2-channel barriers, so you need 6 in an installation (10-channels + 1 channel for the cable loopback test).

We stock a set of 6 of the P&F barriers as one FOG-ISB.

Here’s an Illinois installation – the LIT and 24v power supply in the top right and the intrinsically safe barriers at the bottom: