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?

  • 1
    In my opinion, any high-draw piece of equipment should have one. But that doesn't mean that it's required or necessary. Jan 8, 2018 at 19:54
  • 2
    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 8, 2018 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. Jan 9, 2018 at 5:51
  • 5
    @AaronFranke -- I'd rather have a properly double-insulated appliance than a grounded one, even... Jan 9, 2018 at 12:37
  • What about a grounded insulated appliance? Jan 9, 2018 at 19:51

3 Answers 3


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.

  • 1
    Thank you for a satisfactory answer. Will use equipment as is. Jan 8, 2018 at 14:06
  • 17
    @EmmanuelSillah - If this is a satisfactory answer, please mark it as the accepted answer for this question.
    – William
    Jan 8, 2018 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 9, 2018 at 18:03

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:

Double-insulated icon

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

  • 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 9, 2018 at 16:25

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.

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