electrical question

[Scott Brown]

hey folks, My name is scott and I wont to say that I really enjoy the forum my question is I have a 30 w explorer, , It has , an internal switcher from 110 to 220 volts , so I can use either one, I would like to use 220, but I dont know how to use the 3 prong standard 110 cord that comes out of the back of the laser, and and find a 220 female that will work with it, or do I just figure out how to wire a standard 110 3 prong 220. Any help would be appreiated.

[Robin Lake]

Hi, Scott --

My name is Robin. Nice to meet you.

The reason for plugs and receptacles of differing configurations is to prevent the machine from being connected to the wrong voltage/current. Instant grief. If you change the laser to 220v be sure to change the plug (or entire cord) on the laser and install the correct outlet.

Here is a web page from which you can select the proper plug/receptacle configuration. I may not be configured as a link (those little link, attachment, font, smiley, etc. icons at the top of the reply window don't seem to be working) but you can cut and paste it into your browser.

http://www.leviton.com/sections/techsupp/nema.htm

Good luck.

Robin

[Joe Pelonio]

I'm curious as to why you want to use 220. Most people don't have a 220 outlet in their home except for maybe the electric stove and/or dryer. The reason the laser comes with that switch is because they are sold in Europe where everything's 220. Normally, if you are in Europe you'd order it with the 220 cable/plug, if in the US with the 110. I don't know of any advantage to switching it, is there one?

[Randy Meijer]

Me too?? A 30 W laser should not come close to taxing a standard 120V circuit unless it is already operating at full capacity. If so it would probably be a better choice to run another 120V circuit unless you need a 240V circuit for future machines??

[Jerry Allen]

The meter will spin half as fast at 220V as it would at 110V.
So for same 8 hours use at 220, it would cost the same as it would cost at 4 hours at 110. However, a 30 watt laser uses about 1000W. At $.14 a KWH that would be $1.12 for 8 hours of 110V, $.56 for 8 hours of 220V.
Between building the cable, and rewiring an outlet 220, it hardly seems worth it. As stated previously, most house outlets are 110V and do not have both legs of 110 running though them from the main box. Therefore, you'd also have to run the other leg of 110 from the main. Unless you are already close to an unused dryer outlet or near a 220 outlet in a garage, which is unlikely, it hardly seems worth it.

[Dennis Perry]

Jerry, Read ohms law a watt is a watt voltage dosn't matter.

Dennis

[Ken Garlock]

[QUOTE=Jerry Allen]The meter will spin half as fast at 220V as it would at 110V.QUOTE]

Jerry, the meter should spin at the same rate since it is measuring WATTs consumed, not voltage or amperage. Watts are the product of volts and amps. If you run your machine on 120V and draw 2 amps, for example, and you rewire it to 240V, it will draw just 1 amp, the total power consumption is the same: 120*2= 240 watts, 240*1= 240 watts.

Perhaps some learned EE graduate can explain this with authority.

[Jerry Allen]

Sorry. I'm not awake. You guys are right, except possibly for a minor amount of voltage loss difference at the two voltages, which is probably negligible. When wiring a house, balancing the load between the two 110V volt legs can make a difference in power consumption.

[Hale Reider]

I am looking at a LaserPro 60 watt machine. They recommend 208/220 (on brochure and specification) for the 60 watt, supposedly required for 100 watt. The 60 watt will run on either 110 or 220. They said it was more consistent on 220. Someone else, dealer for a differenbrand, told me last year that tube life was better if you ran on 220 also. In home installations, there is two wire 208 w/ ground and three wire 208 w/ ground. You usually see two wire with air conditioner and water heaters, three wire with stoves and dryers. Home Depot sells a 250 volts two wire w/ground extension cord that I was planning on getting.

I still have some questions before I rewire anything.

Hale Reider

http://tobecherished.com

[Jerry Allen]

Hale,
The reason for the third wire (neutral) is that the motor in a dryer, not the heater element, is still running off 110, and still needs the return line. The laser is probably using a switching power supply and converting all required voltages internally and so you probably just need two wires.
Despite my incorrect previous post, 220 is still more efficient (but not double), due to less line voltage fluctuation, heat loss, and which is preferable for motor start up and overload, and in the case of a laser, should give you a more consistent beam and be easier on the electronics.

[Randy Meijer]

I am looking at a LaserPro 60 watt machine. They recommend 208/220 (on brochure and specification) for the 60 watt, supposedly required for 100 watt....

Given what Jerry said about a 30W machine requiring 1000 watts, it is easy to conceive that a 60 watt machine would just about max. a 20 amp 120V circuit and that a 1000 watt machine would have to be on a 240V circuit. Very interesting.....never realized that these guys created such a heavy load. Learn something new every day!!

[Hale Reider]

I will post one more thought, to see if others agree with me. My 40 watt XXXX laser is leaving the building. I had a dedicated 20 amp line run for that laser with 12 2/w ground wire. My plan is to change out the 20 amp double wide breaker and replace it with a double 15 amp. From what I have read, the white wire, which normally goes to neutral, should be taped red. Connect the white/red wire to a 15 amp breaker and the black to a 15 amp breaker that plugs in to the next lower slot. Because my panel alternates legs where the breakers plug in, everyother one picks up the other leg, or you could connect to a breaker on the other side. At any rate, this gives me 220 volts running through the same wire. Load should be about half of what it was at 110. Ground stays on neutral or grounded. Change the receptacle at the wall and buy the $12.00 extension cord. Breaker is $8.50 and recpetacle is $5.

Is this correct, or.............

Thanks, Hale

http://tobecherished.com

[Jerry Allen]

Randy,
The laser output is not directly proportional to the AC input.
As far as Laserpro Mercurys go, the 25-40 watt machines use 1100Watts, and the 60-120 watt machines use 2000 watts (According to the manual).
That means you still need about 10 amps.

Hale,
The 12 ga. wire is rated 20 amp, so I'd still go with a 20 amp breaker.
Using red tape at both ends of the wire is UBC acceptable. Just make sure that white wire is not shared on a another 120V circuit otherwise you will blow something and/or start a fire!
Usually breakers in one line alternately have access to both sides of the buss. If possible I'd move/rearrange the breakers around until they are right next to each other and get the type that can take a little bar that makes them both flip at the same time. It's not cool to flip one and maybe leave the other hot.
I assume you meant that you are replacing normal breakers with half height ones. There should be 20 amp as well as 15 amp ones.

[Hale Reider]

Thanks for the reply and the help. I didn't see any reason to run new wiring. Hale

[Randy Meijer]

Randy,
The laser output is not directly proportional to the AC input.
As far as Laserpro Mercurys go, the 25-40 watt machines use 1100Watts, and the 60-120 watt machines use 2000 watts (According to the manual).
That means you still need about 10 amps.....

Hey Jerry: I'm a little confused? According to my math, a 2000 watt load will draw about 16 and a half amps. That is right at/or a hair above the upper limit of a 20 amp 120V circuit if you hold to the 80% figure. Guess that is why they suggest 240V for the bigger lasers??