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 appropriate off-the-shelf barrier.

Wastewater Level has tested two barriers and approved them:
– R Stahl: 9002/77-220-146-001
– Pepperl & Fuchs: Z967

Both of these are 2-channel barriers, so you need 6 in an installation (10-channels + 1 channel for the cable loopback test), however, their footprint is quite small, each barrier is about the size of a deck of playing cards. Each Stahl barrier is 0.5″ x 4.1″ x 2.8″ (WxHxD).
And we’ve negotiated some good pricing when these are purchased for a FOGRod system. Contact us for more information.

An installation in Illinois – the LIT and 24v power supply in the top right and the intrinsically safe barriers at the bottom: