My new mill

Discussion on all milling machines vertical & horizontal, including but not limited to Bridgeports, Hardinge, South Bend, Clausing, Van Norman, including imports.

Moderators: GlennW, Harold_V

User avatar
Harold_V
Posts: 20231
Joined: Fri Dec 20, 2002 11:02 pm
Location: Onalaska, WA USA

Re: My new mill

Post by Harold_V »

That will work just fine, although I don't know if that would violate code, or not. If you had to do any work on the light, you'd have to disconnect the machine at the source to ensure safety (or disconnect where it was wired at the machine).

Harold
Wise people talk because they have something to say. Fools talk because they have to say something.
John Hasler
Posts: 1852
Joined: Tue Dec 06, 2016 4:05 pm
Location: Elmwood, Wisconsin

Re: My new mill

Post by John Hasler »

The light needs its own fuse on the primary side of the transformer.
RSG
Posts: 1541
Joined: Fri Feb 04, 2011 9:59 am
Location: Ontario, Canada

Re: My new mill

Post by RSG »

Thanks for the info Harold and John!

John, could I just put a fuse in-line with the power cord?
Vision is not seeing things as they are, but as they will be.
RSG
Posts: 1541
Joined: Fri Feb 04, 2011 9:59 am
Location: Ontario, Canada

Re: My new mill

Post by RSG »

Harold_V wrote: Tue Aug 21, 2018 3:57 pm If you had to do any work on the light, you'd have to disconnect the machine at the source to ensure safety (or disconnect where it was wired at the machine).

Harold
That would be fine as I basically unplug the machine after use anyway. Just a silly habit I have with all my equipment.
Vision is not seeing things as they are, but as they will be.
John Hasler
Posts: 1852
Joined: Tue Dec 06, 2016 4:05 pm
Location: Elmwood, Wisconsin

Re: My new mill

Post by John Hasler »

RSG wrote: Tue Aug 21, 2018 7:56 pm Thanks for the info Harold and John!

John, could I just put a fuse in-line with the power cord?
Yes.
RSG
Posts: 1541
Joined: Fri Feb 04, 2011 9:59 am
Location: Ontario, Canada

Re: My new mill

Post by RSG »

Thanks John,

So that leads me to my next question, looking on line for what size fuse I need I found a formula of Watts divided by volts. So my 50 watt bulb divided by 220 volts should be some where around .25 amp fuse. Does this sound right?
Vision is not seeing things as they are, but as they will be.
John Hasler
Posts: 1852
Joined: Tue Dec 06, 2016 4:05 pm
Location: Elmwood, Wisconsin

Re: My new mill

Post by John Hasler »

RSG wrote: Wed Aug 22, 2018 9:34 am Thanks John,

So that leads me to my next question, looking on line for what size fuse I need I found a formula of Watts divided by volts. So my 50 watt bulb divided by 220 volts should be some where around .25 amp fuse. Does this sound right?
Use 1 amp. A .25 amp fuse is guaranteed to eventually blow at .25 amp.
User avatar
GlennW
Posts: 7284
Joined: Sun Apr 15, 2007 9:23 am
Location: Florida

Re: My new mill

Post by GlennW »

You are basically protecting the wiring from damage in this case, not the bulb.
Glenn

Operating machines is perfectly safe......until you forget how dangerous it really is!
RSG
Posts: 1541
Joined: Fri Feb 04, 2011 9:59 am
Location: Ontario, Canada

Re: My new mill

Post by RSG »

Thanks for the info John and Glenn.

That's what I'll do!
Vision is not seeing things as they are, but as they will be.
User avatar
ctwo
Posts: 2996
Joined: Tue Mar 27, 2012 12:37 pm
Location: Silly Cone Valley

Re: My new mill

Post by ctwo »

I am thinking of my mill, the RF30 which as a light bulb that looks like a factory thing. It used 110V lamps and I suspect taps one of the hot legs to the mill (220V single phase). I'm sure that is hard wired and not fused. Perhaps that is OK, as it is form almost any house lamp with a plug, not to have a fuse, maybe because it is integral to the system?

So, is it the transformer that necessitates the fuse or the lack of a plug?

On my CNC, I tap one hot leg there too, but have a power strip with a circuit breaker on it. That is where I plug in my Ikea 5V LED lamp. It uses a wall adapter (transformer), and perhaps that little plastic brick has an inaccessible fuse? It is plugged, but perhaps I would have hard wired that transformer.

It is true, I think the fuse is not to protect the bulb, but to protect the wiring and transformer.

This became interesting to me when I acquired a 10 outlet strip. It has 10 30A receptacles (I think those are 30A, with the one prong turned 90°. The plug has a prong turned 90°.
It's great because now I can plug in all my 30A devices into that 10 outlet power strip, and draw up to 300A through that cord, but the 30A fuse at the service entrance will protect it from even just two 30A loads, or enough more than just one.
Standards are so important that everyone must have their own...
To measure is to know - Lord Kelvin
Disclaimer: I'm just a guy with a few machines...
User avatar
Harold_V
Posts: 20231
Joined: Fri Dec 20, 2002 11:02 pm
Location: Onalaska, WA USA

Re: My new mill

Post by Harold_V »

A lamp is its own protection, as the resistance of the filament restricts the amount of amperage that can be carried. If voltage is increased, more amperage is forced through the circuit, at which time the filament fails----so it is nothing less than a fuse---one that puts out light.

Fuses are used to protect wiring. They do not protect components, although there are likely cases where they do. Bottom line is that's not why they're used.

H
Wise people talk because they have something to say. Fools talk because they have to say something.
User avatar
Harold_V
Posts: 20231
Joined: Fri Dec 20, 2002 11:02 pm
Location: Onalaska, WA USA

Re: My new mill

Post by Harold_V »

ctwo wrote: Wed Aug 22, 2018 3:14 pm and draw up to 300A through that cord,
A good example of the fuse being used to protect the wire. There's no way in hell the cord used could conduct that kind of amperage. It would burst in to flame instantly if it could, and did. Wire size is way too small to do so.

H
Wise people talk because they have something to say. Fools talk because they have to say something.
Post Reply