2-prong with flat slots?

Can anyone remind me what the flat slot outlets were for? This one is in an upstairs room, 1940’s house. All others are old standard 2-prong or ungrounded modern outlets.:-k

old outlet.jpg

If My memeory serve me right with this old repectale the double " T " slot type it was sorta like dual rated for both 120 and 240 volts.

and that is strictaly a 15 amp repectale

i did see few around here in my area but not too many left around here nowdays.

Merci, Marc

It’s amazing what a new face plate can do to an old receptacle. I’ll remember that trick next time the HI comes round.

Current 20 amp outlets have one slot in a T configuration so that the slot can take either a 15 amp plug or a 20 amp plug. I suppose older ungrounded 20 amp outlets (I have never seen one before) would have both slots in the T configuration so that the 20 amp plug could be inserted either way.

Jim King

I had to read that a couple of times, Jim, current meaning modern, I think, not amps.:stuck_out_tongue:
Yes I found the Carson Dunlop illustration for the flat slots and they are for a 20 Amp circuit, 120 volts, not 220 as a few people, including my client, insisted.


Here’s that illustration.

If you put that flat slot on the other side it becomes a 6-20 (240v 20a)