Anyone had issues with wiring 208V rotos from China?

My electrician is telling my any normal 208V has 2 lines and a ground. However our RF series roto from touchscience has a ground a line and a neutral which their telling me is 110V. However touchscience swears up and down that it is 220V and no one else has had any issue with wiring.

I’m just concerned how positive my electrician is about it being 110V and how 100% positive touch science is about it being 220v

I’m just clueless when it comes to electrical work. Anyone have any input that’s gone through this issue? Going to have them just wire it up and if there’s an issue touchscience is going to have a bad time from me and all my consultant clients that use them. (My clients usually use 110V models since they’re smaller labs, so haven’t rly had this issue before, or their electrician just had no issue wiring up the pseudo 220V wiring)

Everything ive ordered feom touchscience is always 220. You have to ask and pay ecyra for it to be 110. I am not an electrician just my experience dealing with ben

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For ours, the wires were the colors of 110V but they use different colors over in China. If it says 220 on it connect two hots and a ground and you should be good to go

It should say on the equipment if it’s 220v. If it is you’ve got 2 hots and a ground ask touch science what the correct hots color code is

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There are three different combinations:

  1. one hot, one neutral, and ground: 120V circuit.
  2. two hots, no neutral, and ground: 240V circuit.
  3. two hots, neutral, and ground: 240V circuit + neutral, and/or two 120V circuits with a common neutral.

some things like a dryer and other 220v things here in the states are option 3, but option 2 is also used. If your electrician can’t hook up that roto, find a new electrician… that’s some basic stuff.


So it’s 1 hot 1 neutral and 1 ground… but they are 100% positive it’s 220… it’s makes NO sense.

Just because the color of the wire may be black, white and ground, it can still be 220v. A lot of electricians will use the neutral wire as a hot leg instead of running a new wire. Easy way to tell is to check the breaker box for that wire, which im sure the electrician did. It could still be hooked up 110 when it’s supposed to be 220v. motors and heating elements can run 110v but will have a higher load on the system. If its supposed to be 220 and hooked up to 110 its putting more strain on the equipment and also not running efficiently. Swiching to 220v will make the motors and such run at higher rpms with less load, savings with the electricity bill as well.

So have them hook up the neutral as a hot?

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I really gotta learn more about electrical needs. So clueless when it comes to anything more then the absolute basics.

Until one hooks the electrickery up, those three wires from the machine are just that, wires from the machine…the machine does not produce electrickery.

the only way to define one as “neutral” is to hook it up thusly. wire it to the neutral on a 110 circuit, and that’s what it is. connect it to a conductor with 110V compared to ground, and that’s what it is. hook the line and neutral up backwards? you’ve moved the switch, but the machinery should still run.

there should be a label stating 220 on the outside of the machine, along with the current draw at that voltage.

In the case of a rotovap, with a motor and a heating element, the motor may run, but wont be happy. the heater will work, but at only about 1/4 of the power.

imo (not an electrician) your electrician is wrong, and I don’t understand what they’re using to get there.


I don’t want to be responsible so the text book answer is to contact an electrician lol but yes for all of our china imported 220v equipment it was 2 hot legs and a ground. Ground is the easy one, connected to the frame of the roto, and the two hot legs for our roto goes right to the PLC. Even though they look white and black, at the panel each of those wires goes to a 110v leg, making it 220v

have them define why the ___ they are so certain it’s neutral. if it’s based on the color of the wire, poke out their eyes with a sharp stick so they don’t make that mistake again :wink:


It’s not the color even, I confirmed with touchscience that it 100% has 1 neutral line 1 hot line 1 ground line… WHICH IS FREAKIN 110V!!! But touchscience says it’s 100% 220V as the machine is also labeled 220V.

I’m by no means doin this myself my electricians are doing it.

But the fact that touchscience is telling me over and over 1 of the lines is neutral when there’s only 3 lines tells me touchscience has no idea what they’re talking about either…

So somehow I need to get them to change the neutral wire that’s there to a hot line

Electricians just don’t want to mess up but are being told a million different conflicting things. So I guess it comes down to can they just hook up what they’re telling me is neutral into making it a hot line instead and be done with this electrickery?

208v sounds like a three phase thing. At least that is where I would see 208v used, in data centers with three phase power.

gotcha. no need to poke the electricians eyes out then :wink:

when in China, that is how 220 is delivered from the wall.
also NZ, Australia, and much of Europe.

when they double up on the “hot”, they get 440.

machine needs 220V wiggling back and forth between those two conductors. it doesn’t give a rats ass what you call or how you color the wires. in the US you need two hots to give you 220v of wiggly. in China they use one.

I am floored that your electrician is stuck on this.


stealing this. Love it.

isn’t that what the glyph on my multi-meter means?

I’m an electrician. The vap should have come with a wiring diagram. A lot of times they use the wrong color wires or they use the Asian standard of brown and blue. Post the diagram if you have it.

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