220 Volt Plugs

Maybe this will shed some light on it

Yes, different standards and current capacities:

Jon

years so we bought a replacement. It's essentially the same heater except that the new one is a different color and the plug is a different configuration. The old one has one round pin and two flat blades, with the blades at an angle to each other and above the round pin. The new one also has one round pin and two flat blades but the blades are lined up with each other, so I have to replace the receptacle with one that matches the new plug. Not a major project, just a minor annoyance and expense.

some have an L-shaped blade instead of the round pin, others have four blades in a circular pattern which lock when turned, etc. Is there any practical reason for all these variations?

Some are based on different ampere capacities. In 110 volt plugs, a config like this:

| | O

is 110 / 120 volt, 15 amp.

Plug like this:

- | O

is 20 amps.

You hacked the code for Pac Man?

Paul-

It is common to purchase a new appliance without the electric cord. You would specify which connector is required for the cord, and purchase the cord separately. For my dryer, there were two standard versions, "new" and "old" style. To be sure, I made a photo and printed it to show the salesman.

Unless your new water heater has a significantly higher current requirement, it may be easier to change your water heater cord for one with the correct connector, than to change the outlet. You might be able to salvage the cord from your old water heater if it is still in good condition.

Fred

Greenhouse heater, most likely to heat the air. Still, may be possible to use the old cord.

I could use a little more light to be shed...

Why do they use the text "Welder or Plasma Cutter" above the L6-20 and L6-30 plugs?

Are there no other devices that use a locking 20A or 30A plug?

Tons. They just noted the common uses for some of the configurations.

To the OP, you can't just change the receptacle style randomly, you have to ensure that the circuit is the correct voltage and Ampacity to match the receptacle and also the device you intend to connect. Those different styles exist to prevent people from plugging a 120V device into a 240V circuit, or a 50A device into a 20A circuit or similar.

There are two theories on this.

One is that aliens from various planets use different kinds of plugs and so different kinds of sockets are sold.

The other is that hobos can tell from the socket if they are likely to get a handout or get chased away with a gun.

Are you sure the old heater was 240v? The plug you describe is a 30a 120v plug.

The new heater would "work" on 120v but at about 1/4th the output.

Different amperage ratings, for 1.

MANY devices have "custom" cords that would be difficult to swap out for something else - and by changing the cord you can violate the CSA or UL certification of the device.

placement. It's essentially the same heater except that the new one is a di fferent color and the plug is a different configuration. The old one has on e round pin and two flat blades, with the blades at an angle to each other and above the round pin. The new one also has one round pin and two flat bl ades but the blades are lined up with each other, so I have to replace the receptacle with one that matches the new plug. Not a major project, just a minor annoyance and expense.

e instead of the round pin, others have four blades in a circular pattern w hich lock when turned, etc. Is there any practical reason for all these var iations?

Yes, it was a 240v. On the link

the original plug is in row 7, 20R, while the new one is in row 6, 30R. The new heater is rated at 30 amps.

Thanks to all for their comments and links.

Paul

That 7-20R is for 277v, (the L/N of 480v wye).

Again it would work on 240v but at lower power.

Welders operate on a duty cycle, so code allows you to "downgrade" the wire size from the listed amps of the unit, since the unit cannot be run continuously.

The outlet has to be labeled that it is specified for a welder, though, so nobody plugs in a continuous-duty appliance.

Jon

Generators often have locking recepticles, maybe because of the vibration loosening non-locking plugs.

and it sounds like OP might have a 10-50 recep and a 6-15 plug, don't really want to be plugging a 15 amp or less device into a 50A circuit, unless the device itself has a main fuse or breaker. Important concept is recep amp rating must match the breaker, except in the instance of a

nate

just after I posted I realized that it might in fact be a TT-30 not a

I've seen other 220 volt plug configurations; some have an L-shaped blade instead of the round pin, others have four blades in a circular pattern which lock when turned, etc. Is there any practical reason for all these variations?

Paul

No Paul there are no reason the only reason that could find that our OSH system is politically oriented like Washington.