Wiring advice for small single phase lathe in home workshop

Question

I am being asked to wire up a small single phase lathe in a home workshop. 
 I will be using an NVR switch for start and stop, with a 0.55kw motor looks like I should have overload protection as well (552.1.2) 
 The customer has an old forward/reverse switch, my guess is 30 years old with metal case , but looks in good condition. My specific concern is that the switch has a leaver to rotate it and a center off position, it could easily be used to switch the motor off and then knocked on. The customer is quite safety conscious so fairly unlikely to happen, but I am wondering if this is normal or is there an alternative arrangement used? Just realised I my have to change the switch anyway as it's not ip rated, but still not sure what to use. 
 Tried to attach some pictures but cant work out how to do it?

Chris Pearson · Answer

I cannot quite see why the lathe should not be put on a plug. 
 If this is the sort of switch that you mean, I never had a problem over almost 4 decades.

Chris Pearson · Answer

Once you put the lathe on a plug, it falls outside BS 7671. 
 If you want to get all H&S about it, you'll need that emergency stop button and a brake for when your sleeve or tie gets caught up in the chuck.

gkenyon · Answer

Hi John Peckham , Not saying this type of lathe can't be connected, or shouldn't be used, but it's potentially a tricky situation for a professional electrician if anything were to go wrong, especially as for a domestic Client ... you effectively take on all the CDM duties as well as Building Regs bits and pieces etc, PLUS any replacements, mods or wiring within the "machinery" (say of reversing switch) the relevant bits would be to standards other than BS 7671? 
 Perhaps not a "don't ever go there" position. Would a suitably worded contract help sort out some of the tricky legal issues? 
 I would guess it's easier (in terms of exposure to a lawsuit) on the electrician or contractor if the same situation came up for commercial/industrial installation (although there'd still be a duty to at least point out any deficiencies the contractor was aware of, for a decision by the Client)?

gkenyon · Answer

Apologies, also in the above, I meant to mention something specific. 
 Alan B said: The customer has an old forward/reverse switch, my guess is 30 years old with metal case , but looks in good condition. My specific concern is that the switch has a leaver to rotate it and a center off position, it could easily be used to switch the motor off and then knocked on. 
 So, the main reasoning for mentioning the fact that BS 7671 isn't the standard, is that replacing this switch would not be covered in BS 7671 - out of scope - and other standards, including BS EN 60204-1 and BS EN 60073, plus other attendant standards, would have to be considered. Which causes a plethora of issues, potentially, with older equipment.

Wiring advice for small single phase lathe in home workshop

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