It's entirely normal for a spark to occur if the plug is pulled while the appliance is using electricity.

Thanks! That may be the case as the spark is random.

OK, so pulling a plug from an outlet and getting a spark is normal because the appliance is still pulling electricity. What about plugging the appliance *in* to an outlet? Why is it that I get a spark in some outlets and not others with the same appliance? Does this indicate a problem between outlets?

TIA!

It doesn't matter whether you're "plugging in" or "pulling out" from a receptacle. Sparks are pretty much guaranteed if the device is drawing electricity. The only variable is whether or not you happen to see the spark.

Ah ... so one outlet might be in a darker place than another. And bottom line is, seeing a spark as you draw out the plug from a working appliance isn't (in itself) indication of a problem. I think.

Thanks!!

Over time it may become a problem. If the device or appliance has an on off switch, turn it off then un plug. The cord and receptacle are not neccessarily designed as the disconnecting means.
Over time this will start to degrade the prongs on the cord and also can do damage to the receptacle.

"The cord and receptacle are not neccessarily designed as the disconnecting means. "

Actually, they are.

That does not mean they are designed for repeated use in this manner.

It's one of those plug-in hot water heaters, an old one and not one of the 'appliance-types', IYKWIM. The kind where the bottom pan is metal and just heats up. Anyway, definitely not designed for an on-off switch. Though I could plug it into an extension cord I stuck an on-off switch inline onto many years ago....

"The cord and receptacle are not necessarily designed as the disconnecting means. "

Yes they are. I have a George Foreman knock off grill and a small deep fat fryer neither of which has an on/off switch. They have an internal switch that cycles when they get to temperature but only the plug for on/off.

For many electrical units, the cord and plug is deemed the "disconnect" per the NEC since there is no on/off switch.

I have a new Bissell vacuum which sparks when I plug it in. It is turned off so I would expect it not to arc/spark. The fact that it does and is taking pieces of metal from the plug end has me concerned. This means that over time my sockets will also be getting arced corroded as well. I wrote Bissell about this and they told me this is normal just like a TV or computer. Well a vacuum isn't like those at all. When the switch is off the black wire (hot) should be going no farther than the switch internally. The fact that it is drawing current when the switch is off means something is wired wrong. Or, maybe they put a relay as the Power-on switch. Then the arc is caused by the build up in the coil. Does this sound correct? At first I thought they had the Line and common reversed. In any case, eventually this will cause problems with the sockets in my house, won't it?

Eventually. In about 70 years*. Don't worry about it.

*Yes I made up the time frame. But my point is that this is a pretty typical occurrence and won't cause significant damage.

"It is turned off so I would expect it not to arc/spark."

Depending on how the device is designed, "turned off" may not be zero power draw.
This is more andmore common with items using electronic controls.
The controls need power to then turn the device fully on, so the electronics are 'always on.'

You know, in the Antipodes, where it's 240v, every outlet has a little on/off switch. Makes a lot of sense, really.

Many of the small appliances described are used on a kitchen counter top and should be plugged into GFCIs. This may not prevent an occasional spark, but they will prevent you from being shocked by a defective appliance.

"You know, in the Antipodes, where it's 240v, every outlet has a little on/off switch. Makes a lot of sense, really."

At 240 V maybe, but not at 120 V.