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.

Well, Touchplate decided to get rid of it!

Relax though… there is a quick and painless workaround.

This is from the website myelectric.net:

“Although the 4000-PL is not an official direct replacement for the discontinued 2500-B, 2500-BPL, it has been verified by the manufacturer that this unit (4000-PL) can be used. The only real difference is that the 4000-PL has high voltage screw-terminals, where the 2500 already had some #12 wire connected. In fact, if you are using the 4000 to replace the 2500-BPL, its (in almost every way) a direct replacement.

If you are using the 4000-PL to replace a 2500-B (without the modular plug), then you will need to cut the plug off of the end of the 4000-PL. Touchplate says it will substitue just fine, both yellow wires are for the pilot, and the red and brown are the switch wires. For the high voltage side, you will need to screw in your wire. (#10 max.)

You’ll really only run into trouble if your current panel is packed full. The base of the 4000-PL is about 3/4″ wider (see picture below) to accomodate the screw-in terminals on the high voltage side.”

So, you can see that there is no cause for panic, any old Touchplate systems which you are still maintaining will be, well, maintainable for quite some time.

Of course, if your system looks like the picture below, you might want to consider making some changes. =)