ECN Electrical Forum
Discussion Forums for Electricians, Inspectors and Related Professionals

It’s too bad because the InterLockits are a decent product and it’s the tish faces at Wyle that got paid to provide the needed credentials that have screwed them over.
A few years back, I installed one of these on a SQD QO panel and it worked perfectly, but as you can guess, SQD has since issued a notice about how using these devices from other manufactures on their panelboards will void their warranty. No surprise that SQD now offers a very similar interlock switch pre-installed as a listed assembly on some of their panelboards… at a premium price. I really don’t understand this BS because the only electrical component is the circuit breaker that is being backfed from the generator and that comes directly from the panelboard manufacturer themselves anyway. You have to assume the whole thing was only about SQD being miffed that they weren’t getting a bigger piece of the pie.

The operative word in 110.2 is "approved". 90.7 gives you the assurance that if a NRTL lists an item you don't have to inspect it further but there is nothing that says the AHJ can't approve an unlisted device if it is inspected and deemed safe. That is really why we have 90.4