We had a friend come to us the other day wanting to find a replacement for an old Square D relay.

Square D relay??? Man, that system is from the ’50s. This seemed like it might be impossible, but actually, it’s not. Back in the 50’s, Square D sold some(or all, not 100% sure) of its low voltage line to Pass&Seymour. Pass and Seymour manufacture the modern version of this relay in the 1070B. The old Square D catalog number was 1070A.

Anyway, as you can see from the picture below, the 1070A and B are virtually identical. The only real difference is that the 1070B has a slightly larger shaft, but with its thinner nylon retaining ring, it should fit in the panel as intended. On the inside, the upgrades are somewhat more significant. The old 1070A was AC only. The 1070B can differentiate AC/DC, and the new relay can handle 20Amps, while the old one was rated at 15.

Check out our link to the right (MyElectric) to purchase this relay.