Shenhui wiring

[Eric Ucci]

So, now I have these 2 machines which have European wiring as far as I can tell and I'm trying to come up with a reasonable wiring strategy.
i plan on running a sub-feed panel to each machine to power the 5 basinc components that need to be powered.

i plan on using this switch for the 220vac components;
http://www.ebay.com/itm/ws/eBayISAPI...E:L:OU:US:1123

and these for the 110vac components;
http://www.ebay.com/itm/ws/eBayISAPI...E:L:OU:US:1123

i plan to mount all of the switches in this box next to the sub-feed panel with easy operators reach at each machiine;
http://www.ebay.com/itm/ws/eBayISAPI...E:L:OU:US:1123

Now, I'm trying to size the sub-feed panel and this European wiring has me a bit confused
Here are my basic setups

SH-1490
150w reci
1. laser power supply 220vac (28mA or .028A according to Joy at Shenhui)
2. Stepper motor & control power supplies 220vac (2.5A according to Joy at Shenhui)
3. CW-5000 chiller 220vac (max 2.1A printed on label)
4. Penn State 2hp exhaust blower 220vac (8A)
5. Air pump 110vac t.b.d.

SH-690
60w standard tube
1. laser power supply 220vac (15mA or .015A according to Joy at Shenhui)
2. Stepper motor & control power supplies 220vac (2.5A according to Joy at Shenhui)
3. CW-5000 chiller 220vac (max 2.1A printed on label)
4. Harbor Freight 1hp exhaust blower 110vac (8A)
5. Air pump 110vac t.b.d.

Here in the States, I can't find a double pole breaker less than 15A. i had originally planned on a dedicated circuit for each of the components. However, now that seems a bit overkill. Why put a .028A load on a dedicated 15A breaker?

For the SH-1490...
the 2 plugs at the back of the machine + the chiller should be wired to the same breaker. The 220 vac blower could be on its own dedicated circuit. and the 110vac air pump on a third. (3 circuits total)

For the SH-690...
the 2 plugs at the back of the machine + the chiller should be wired to the same breaker. The 110 vac blower and the 110vac air pump on a second. (2 circuits total)

What do you folks think?

Of course, I consider all input as no-binding suggestions by persons not representing professional opinions ;P

I have an electrician coming by on Mon. i just wanted to run it by all you ladies and gents.

thanks

[Eric Ucci]

One minor addendum...
The amp ratings I posted previously are, in fact, the output amperage measured at the dial indicator near the LCD on the laser.
The actual amp rating on the input side is .8A for the 150w laser and .3A for the 60w laser. Still small enough not to change my original estimate.

[Rich Harman]

I run the laser (laser power and the rest), the CW5000 and the exhaust fan all off the same 220V circuit. No problems at all. I even run my bandsaw off the same circuit at the same time.

[Eric Ucci]

Rich,
That's encouraging. It means that my sub-feed only needs 3 slots (2 for the 220, and 1 for the 110) which is inexpensive and not as huge as i had earlier expected.

Thanks

[Bill Jermyn]

As an electrician,

You mention that you're unable to find a breaker less than 15 amps. The size of the breaker does not need to match the current consumption of the device (of course it cannot be less).

The purpose of a breaker is to protect the wires.

If the device requires protection for its internal components, the device itself should have appropriately sized fuses, breakers or other mechanisms onboard.

Not sure what the Chinese practices are in this regard, but if the device has a UL or similar certification (the certification, if it has it, will be shown as a symbol on the device's nameplate located on the exterior of the device), it will be properly internally protected and the panel breaker needs only to be sized to protect the wires between the panel and the device.

If the device doesn't have UL or similar certification, I would not use it. If it causes a fire, you insurance policy will not pay damages.

For a 15 amp breaker the wiring from the breaker to the device must be #14 A.W.G. or larger.

[Dan Simone]

At least on my recently acquired machine there are two smaller fuses at the machine. They look to be 5A fuses if I had to guess.

[Eric Ucci]

For a 15 amp breaker the wiring from the breaker to the device must be #14 A.W.G. or larger.

Bill,
My AWG chart shows max Amps for 14awg wire to be 5.9A (in a douple pole circuit this would correspond to 11.8A)
Thus, requiring 12awg wire for a 15A circuit

How did you arrive at 14awg?

[Bill Jermyn]

The current rating for wires depends on their application and location.

#14 is rated at 5.9 Amps for chassis wiring. This takes into account the fact that the wire may be operating in an enclosed space in proximity to heat sources (heat dissipation is the limiting factor for wire size).

For wiring between a panel and a device (i.e. normal house wiring) it is rated at 15 Amps. That is from my electrical code book, but it's also available online, for example:

http://electrical.about.com/od/wirin...twiresizes.htm

Oh, and you can't double the rating if you're using a 2 pole breaker, it's 15 Amps, period (or 5.9 for chassis wiring).

[Eric Ucci]

Bill,

This is why I'll be hiring a professional to do the wiring :P
As you can see, my knowledge on this subject is a bit fuzzy.

Thanks

[Bill Jermyn]

OK, it's like this:

Imagine you're an electron...

Under the microscope electrons look like little M&M's. You can be a green one with a straw hat.

Imagine you're zipping along a wire.

Nah...

I did have a beer with an electron on a beach in Tahiti years ago though, who had been in 3 Mile Island. Boy, did he have some stories to tell...

[Eric Ucci]

Bill,
I received my 2 shenhui machines. Each came w 3 of these plugs rated at 220vac 10A. (see photo). 2 go to the back of the machine (one for laser, the other for stepper motors w controls). The 3rd plug goes to the chiller.
120 & 122.jpg
they are labeled L, N, & E.
when I search online, it appears that in Europe this corresponds to L=live, N=neutral, and E=ground.
Correct me if I'm wrong, but in the US there is no "neutral" in a 220 circuit.

Should I assume that L & N are the 2 hot legs on a normal US 220vac circuit?

Rich, Is this the same type of plug that you have with your machine?

and another thing...

Do i need to be concerned about the European 50 cycles compared to US 60 cycles?

Thanks again for all the help!

[Rich Harman]

Yes, I just chopped those off and put on my own plugs. Two hots and a ground. The neutral in this case is the other hot.

[Bill Jermyn]

Your assumption about the pinouts is probably correct, but I'd check with the manufacturer or distributor.

As for the frequency, I'd definitely check with them as well. I'd be most concerned about the chiller. Motors (particularly their starter circuits) can be finicky about frequency, to the point that the pump motor may instantly be permanently damaged. Also, the pump (assuming it has an AC induction motor) will run 20% faster on 60 Hz. This may or may not present a problem, I don't know.

I'd err on the side of caution before you fire it up.