Does a 2100W angle grinder need an earth pin?

Question

I have recently purchased a Makita 2100W angle grinder. It has just the live (L) and neutral (N) connectors unlike the one I previously used, which had a third protected earth (PE) connection.

Would it be better if I changed the connections to a 3 pin connector?

In my opinion, any high-draw piece of equipment should have one. But that doesn't mean that it's required or necessary. — Aaron Franke, Jan 08 '18 at 19:54
this is a new(-ish) tool presumably? If you bought something 40 years old at a yard sale that may be a different matter. — agentp, Jan 08 '18 at 21:38
There is also a possibility that your old grinder was double insulated, but just had a three-pin plug or cordset. The cords on grinders tend not to last too long. — SomeoneSomewhereSupportsMonica, Jan 09 '18 at 05:51
@AaronFranke -- I'd rather have a properly double-insulated appliance than a grounded one, even... — ThreePhaseEel, Jan 09 '18 at 12:37
@AaronFranke What does current draw have to do with grounding? The cable is going to supply 120V at over 20A when shorted. — Navin, Jan 10 '18 at 17:41

score 71 · Answer 1 · answered Jan 08 '18 at 13:38

71

Your grinder is a Class-II Double Insulated appliance and therefore does not require a ground/earth connection.

But even if you did decide to fit a 3-pin plug, what would you connect the 3rd pin to?
There's no 3rd wire in the cord, nor is there a ground point in the device to connect it to.

answered Jan 08 '18 at 13:38

brhans

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Thank you for a satisfactory answer. Will use equipment as is. – Emmanuel Sillah Jan 08 '18 at 14:06
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@EmmanuelSillah - If this is a satisfactory answer, please mark it as the accepted answer for this question. – William Jan 08 '18 at 18:01
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If this is indeed a Class-II double insulated, not only is a 3-pin connector not required but likely forbidden. In the Netherlands under NEN3140, in Europe under NEN-EN 50110 and likely in other parts of the world as well. It's considered something along the lines of a false safety measure. – Mast Jan 09 '18 at 18:03

score 20 · Answer 2 · edited Jan 09 '18 at 12:09

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It is double insulated. Your prior one wasn't so its case had to be grounded.

Look for the square in the square icon on the name plate of the device:

You will not be any safer if you replace the plug.

edited Jan 09 '18 at 12:09

psmears

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answered Jan 08 '18 at 13:37

Dan D.

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I believe the square icon isn't required in the US, though it's quite likely present anyway if the tool is sold in Europe. – Phil Frost Jan 09 '18 at 16:25

yo' · Answer 3 · 2018-01-09T21:04:13.813

Well, your modification would very likely worsen the safety.

Either you replace only the plug, it would be just that, a new plug, with the GND not connected anywhere. That makes it worse by giving a false belief that the appliance is grounded.

Or you decide to replace the cord as well. It would mean opening the chassis, finding a connection point somewhere and soldering or connecting the GND wire there. However, you first, can't be sure that the connection point is "good enough". Second, opening the chassis may damage some insulation. Third, the device, as is, was tested against various failures and use conditions, your modification would not be.

Does a 2100W angle grinder need an earth pin?

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