Need help wiring a lathe motor

[chola]

Hi,

I'm doing a motor and switch transplant on my mini lathe.

I have taken the motor and switches from a drill press for this purpose (reason is was more powerful than my lathe motor).

My question is, where is the best place to connect the earth leads to (green and yellow)? The motor will be mounted separately on an alloy plate that is not in contact with the lathe itself, so should I connect both leads to the alloy plate then run another to the body of the lathe to be sure, any suggestions.

I have attached a basic pic of the setup.

Keep in mind this is for Australian 240volts (if that makes any difference) but I would imagine the theory is the same worldwide.

Thanks for any assistance.

Colin

[wjfiles]

There is no need to connect the motor base to your lathe IF your workshop wiring has been done correctly.
The Earth {green & yellow) wires and the common Black or Blue should be Common throughout the whole electrical supply system.
I have seen motors in a home wired workshop connected to a lighting circuit with no earth wire. Only recommended if you intend a short life span.
YOU SHOULD HAVE A QUALIFIED SPARKY LOOK AT YOUR SETUP. He has equipment and knowhow to determine the safety of the installation.
WJF
(another aussie)

[vger]

Connecting the earth lead to the motor frame gives you protection in case the windings in the motor short to the frame. An earth ground is sometimes also provided to the metal part holding the switch's to protect in case a switch breaks and power comes in contact with the metal part. If either of these faults occur it will blow the breaker (fuse) rather than allowing the current to pass through you.
Steve

[Al_The_Man]

I don't know what the Standard is down under, there is CSI, UL, BSI.
But the NFPA wording is:
Equipment Grounding:
The machine and all exposed, non-current-carrying conductive parts, material and equipment, including metal mounting panels that are likely to become energised and are mounted in non-metalic enclosures, shall be effectively grounded.
Anyway, probabally cost about 50¢ to run a bonding wire/strap
Al.