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ray hampton
09-09-2011, 12:24 AM
I replace a plug on a off-set hand held grinder and GOT A QUESTION about the cord and plug, the cord wires are black + white /no ground wire-- is the third blade purpose to require the plug blades being placed in the right hole , how do this tool handle a short-circuit

Dan Hintz
09-09-2011, 7:42 AM
No. The blades end up in the correct hole due to the differing size of the blades, regardless of the grounding blade being there or not.

John Coloccia
09-09-2011, 8:00 AM
I don't think I've ever seen a 3 prong plug with a wider blade. I think they depend on the third prong to get the polarization correct.

re: your grinder

It DOESN'T handle a short. It is "double insulated". The insulation is either multiple layers or a single reinforced layer, and the idea is that a fault cannot occur as a single point of failure that energizes the case. A better solution would have been to replace the plug with the same kind of 2 prong plug it came in. Either way, it's relatively important to get the polarization correct. On old toasters, it was a toss up if the heating element was energized even when the toaster was off. The polarized plug insures that the hot wire is before the switch, not on the heating element side. This is why you're admonished to NEVER stick anything in a plugged in toaster, even when it's off. I'm not sure how important it is in the grinder, but it's certainly good form to have the hot wire going to the switch as opposed to energizing all of the internal circuitry all the time. :)

ray hampton
09-09-2011, 1:36 PM
I understand why one blade are wider in a 2 prong-plug but can you see which blade are the wider when you are trying to plug it in, a 3 blade plug are the easy way

Marty Paulus
09-09-2011, 1:53 PM
I don't think I've ever seen a 3 prong plug with a wider blade. I think they depend on the third prong to get the polarization correct.

re: your grinder

It DOESN'T handle a short. It is "double insulated". The insulation is either multiple layers or a single reinforced layer, and the idea is that a fault cannot occur as a single point of failure that energizes the case. A better solution would have been to replace the plug with the same kind of 2 prong plug it came in. Either way, it's relatively important to get the polarization correct. On old toasters, it was a toss up if the heating element was energized even when the toaster was off. The polarized plug insures that the hot wire is before the switch, not on the heating element side. This is why you're admonished to NEVER stick anything in a plugged in toaster, even when it's off. I'm not sure how important it is in the grinder, but it's certainly good form to have the hot wire going to the switch as opposed to energizing all of the internal circuitry all the time. :)

Ahh now I understand the logic behind polorized plugs. Thinking about it it does make sense now. THanks John!