[sgt panties]

Hi, I am a bit new to metalworking. I'm self-taught and my machine time could best be measured in hours not days. I'm pretty well read, but the one thing they don't cover in the books is how to set up the electrical to power on the machine.

I have a lathe and a mill, chinese, non-CNC, single phase, 1.5 to 2hp, both came with a standard grounded plug, and they are near 20A outlets.

What I'm getting at is I am always plugging/unplugging the machine to use them. They didn't come with an integrated on/off switch unless you want to count the emergency shut off. I unplug because I am in "lightning country", especially in the warmer months there are hits all the time. I prefer not to see what happens when they get hit.

So I guess what I'm asking is how do you ISOLATE your machine? What is the correct way to do this, and how to do it cheaply? Also, a more convenient way to turn them on than plugging/unplugging and wearing out the outlet would be nice.

Thanks.

--tom

[Al_The_Man]

There is actually a book or booklet, called NFPA79 this covers all electrical requirements and details on wiring for Electrical Machinery.
The way it is usually done in a commercial machine is that the electrical and electronic components are mounted in one enclosure, with the exception of operator panels etc.
This allows the MTB to easily implement a single disconnect for the whole electrics, the disconnect as its name implies shuts off all electrical power to the machine.
The secondary disconnect is usually an E-Stop contactor or relay which allows things such as PC or controller to be active but all power devices switched of until a control Push Button is operated.
If you have a machine already built an you want to go with the least effort, buy a fused disconnect from H.D. and wire the necessary sockets after the disconnect, or wire in direct into disconnect if preferred, this could be 120 & 240 sockets if necessary.
Enclosure Disconnects are also available on ebay cheap, these are usually 3 phase but can be used on 1 ph.
Needs an box enclosure ebay 320183877770
Al.

[sgt panties]

Excellent reply. Problem solved. Thanks.

[wizard]

A disconnect is the proper way to isolate a machine from the AC line but don't expect it to save you from a close by lightening strike. Lightening coming from 10 miles away isn't going to have problems with jumping across the air gap in a disconnect.

That being said a disconnect can help with line conducted surges of limited scope. I just wanted to moderate your expectations a bit. It is certainly good practice to isolate with a disconnect but when talking about lightening it isn't a sure thing.

The other thing to consider is investment in surge suppressors and the like. If you are in a area known for lightening issues a good electrician or electrical supply house could fix you up.