2 quick questions...

Hello everyone. This is probably a really stupid question, but I'm working on my reprap, and I can't figure this out. I want to make sure, and the instructions don't say anything. The part that goes into the wall gets hooked up to L and N for the power supply correct? And which color is live and which is neutral? I have a blue wire and a purple wire. Thank you for any help.

2 quick answers:

1 - You really should check with the company that sold you the kit. You mention instructions so I assume you obtained some kind of kit...

2 - If for some reason the company that sold you the kit is unable or unwilling to provide tech support, you need to give us more information before we can help you. Especially especially when you are talking about "the part that goes into the wall". If you make a mistake hooking up wall current you can break things, start fires, hurt yourself, or worse...

This additional information would be helpful:

1. What kind of "reprap" is this? Where did you get it?
2. What country are you in? Wall current conventions differ by country.
3. What kind of power supply is it? What are the blue and purple wires connected to on the ends? A few pictures here would be really handy...

Also, there is an extensive wiki page on power supplies here. You might find your answer on that page.

Typical color codes are black - line, white - neutral and green - ground (in the US at least) and brown - line, blue - neutral, green - ground internationally. I can't say that I have ever seen purple - any chance it's just a funky brown? In any case, multi voltage power supplies these days are not terribly picky about line/neutral reversal, since they will be getting two hot legs (at least in the US) on a 220v service anyhoo. If it's a 120v only power supply, then it may well matter very much . . . In any case, it pays to get it right . . .

- Tim

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tadawson
Typical color codes are black - line, white - neutral and green - ground (in the US at least) and brown - line, blue - neutral, green - ground internationally. I can't say that I have ever seen purple - any chance it's just a funky brown? In any case, multi voltage power supplies these days are not terribly picky about line/neutral reversal, since they will be getting two hot legs (at least in the US) on a 220v service anyhoo. If it's a 120v only power supply, then it may well matter very much . . . In any case, it pays to get it right . . .

- Tim

+1 on this answer. Given the way front ends can be built for SMPS's, this can be critical or not. Always treat as critical. If you can post some info on the power supply, such as make and model, the interwebs can hopefully supply an answer.

Thanks for the replies. I spoke with the distributor, but he was saying the n is for negative in China and the purple is negative, but I know it stands for neutral, so I'm a little worried. I really don't want to mess this up. It's a prusa i3. Here are a couple images. You will see the wall outlet, the wires and the power supply. Thank you for any help.







Edited 1 time(s). Last edit at 04/29/2015 11:25AM by fatesalign.

Sheesh!

Forget the colours.

L and N!

You'll want an earth with that.

That's the end of the printer that will kill you. Ask someone real-life for assistance if you're unsure.

-a

Have you tried using a multimeter?

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DonaldJ
Have you tried using a multimeter?

+1 on the multimeter testing as well. On the two wire plug, the narrow spade is the hot side and the wider blade is neutral. I would ditch that two wire cord and get a three wire cord from a hardware store and used the L, N, and GND terminals. Plus, if you are hooking up a computer to talk to this as well, put both the RepRap and the computer from the same socket.

What will a multimeter tell him?

That AC supply has neither +ve or -ve

-a

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alan richard
What will a multimeter tell him?

That AC supply has neither +ve or -ve

-a

If he has a polarized plug (and a properly wired outlet) a multimeter would tell which colored wire is connected to which spade. So he could could hook up the line to the hot and neutral to the neutral. It likely doesn't matter, but in case it does...

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itchytweed

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DonaldJ
Have you tried using a multimeter?

+1 on the multimeter testing as well. On the two wire plug, the narrow spade is the hot side and the wider blade is neutral. I would ditch that two wire cord and get a three wire cord from a hardware store and used the L, N, and GND terminals. Plus, if you are hooking up a computer to talk to this as well, put both the RepRap and the computer from the same socket.

Thanks everyone. Concerning getting a new wire, will it actually be red and black so I don't need a multimeter?

Also, the instructions said to put a fan and the power for the board into the negative and positive terminals.

Lastly, I can take anything that has a wall adapter and cut it right?

Edited 2 time(s). Last edit at 04/30/2015 04:05PM by fatesalign.

Im not sure how old you are but please have a word with someone who understands mains power in your region or you will hurt either yourself or someone around you.
That power supply needs 3 wires to your wall outlet.
Live, neutral and earth. 2 wires are not safe without that earth connection.

In the Uk we have 3 pin wall plugs. with clearly marked Neutral, live and earth connections. L,N,E

Gordon

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Gordon
Currently have a tweaked mendel prusa i2
About to build a P3Steel.
[scratchpad.thisandthose.org]

Printer for hire.
[www.3dhubs.com]

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gordonendersby
Im not sure how old you are but please have a word with someone who understands mains power in your region or you will hurt either yourself or someone around you.
That power supply needs 3 wires to your wall outlet.
Live, neutral and earth. 2 wires are not safe without that earth connection.

In the Uk we have 3 pin wall plugs. with clearly marked Neutral, live and earth connections. L,N,E

Gordon

I'm not a child if that's your concern. I understand many ac adapters do, but wires that don't have a third prong do not have a ground, so no. Not all power cords have a ground. As a matter of fact, so many power cords dont have a ground that most splitters dont even have the third prong on them. No offense, but the company I bought it from has sold many. No one has been killed, but I simply needed to know which one is the neutral and which is live. I understand no one knows, so I'm willing to get a regular power supply.

It may seem like I have absolutely zero knowledge of wiring, but I do. I'm just not huge on diy electronics, and I had never seen a purple and blue wire before. But while the UK might only have wires with a ground, most don't in America. As a matter of fact, the cell phone charger I'm using right now doesn't have a ground. Don't get me wrong. Im not trying to be rude. I just want it to be understood that I do know enough.

Edited 3 time(s). Last edit at 04/30/2015 07:26PM by fatesalign.

There are good reasons why you sometimes see two pins and sometimes see three. I expect you need three.
My knowledge comes from Australian wiring, but I expect protection methods against electrocution are universal.

Appliances generally use one of two methods to protect you and me from electrocution.

1. Double Insulation (class 2). Accessible parts have (at least) two layers of isolation between them and internal live parts. The only way accessible live parts can become live is if both insulation layers fail. These appliances do not use Earth for protection and so only have the Active and Neutral pins on the plug. (These appliances usually have a symbol on them: one square inside another square.)
2. Earth (class 1). Accessible parts can become live in the case of a fault. Your 12V power supply looks like one of these. It is appears encased in metal and it would be quite possible that if it were dropped and something became loose, or if water got on it, or something like that, the outer case could become live and if you (or anyone) then touched it, you could die!
(there is a '3' - class 3 - for extra low voltage.. such as your car battery.. but that's not what's being discussed here).

As I have said, your power supply needs an earth. This is also evident by the fact that is has an earth terminal. I would not use the the plug they provided if it does not have an earth wire.

Neutral is usually connect to earth somewhere in the distribution system (here in Australia anyway). So identifying Active and Neutral can be done by measuring their AC voltages with respect to earth. Active will be about your phase voltage, and neutral will be about zero.

Quote
blabbersnitch
There are good reasons why you sometimes see two pins and sometimes see three. I expect you need three.
My knowledge comes from Australian wiring, but I expect protection methods against electrocution are universal.

Appliances generally use one of two methods to protect you and me from electrocution.

1. Double Insulation (class 2). Accessible parts have (at least) two layers of isolation between them and internal live parts. The only way accessible live parts can become live is if both insulation layers fail. These appliances do not use Earth for protection and so only have the Active and Neutral pins on the plug. (These appliances usually have a symbol on them: one square inside another square.)
2. Earth (class 1). Accessible parts can become live in the case of a fault. Your 12V power supply looks like one of these. It is appears encased in metal and it would be quite possible that if it were dropped and something became loose, or if water got on it, or something like that, the outer case could become live and if you (or anyone) then touched it, you could die!
(there is a '3' - class 3 - for extra low voltage.. such as your car battery.. but that's not what's being discussed here).

As I have said, your power supply needs an earth. This is also evident by the fact that is has an earth terminal. I would not use the the plug they provided if it does not have an earth wire.

Neutral is usually connect to earth somewhere in the distribution system (here in Australia anyway). So identifying Active and Neutral can be done by measuring their AC voltages with respect to earth. Active will be about your phase voltage, and neutral will be about zero.

I appreciate the great reply. I will probably get another one with a ground. At least that way I'll know where everything goes from the color (grey, yellow etc). And yes, it does have the ground symbol, so I know it's probably made for it.

I did notice that it outputs 20 amps, but I just think that sounds a little high. I remember when I had my other printer, it just had a normal PC power cable, which is only 10A right?

Edited 6 time(s). Last edit at 05/01/2015 12:41AM by fatesalign.

A PSU capable of 20A output @12V is normal for a 3D printer with heated bed. A typical heated bed takes 10A or more by itself. These types of PSU always need a mains ground connection. The current drawn from the 110V or 230V mains will be much lower, e.g. about 6A @ 110V, so a normal PC type mains power cable is suitable.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Fatesalign,
If you havent already killed yourself get a PC ATX power supply mains plug, cut away the connector that plugs into the ATX PSU and strip the outer insulation back, you should end up with a Brown (Live), Blue (Neutral), and Green/Yellow (Earth) wires. Connect these to L N and E respectively.
The above info is for UK/EU wiring. The wiring for US colours is mentioned above (and on wikipedia) as Black (Live) White (Neutral) Green/Yellow (Earth)
If your not sure of what your doing with this mains wiring, get your neighbour to help you or anyone else that knows how to wire a plug.

No offense, but I understand all of that. I understand what colors in America. It was really just the strange colors of the plug that came with the kit that I didn't know.

Edited 2 time(s). Last edit at 05/01/2015 10:41AM by fatesalign.

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dc42
A PSU capable of 20A output @12V is normal for a 3D printer with heated bed. A typical heated bed takes 10A or more by itself. These types of PSU always need a mains ground connection. The current drawn from the 110V or 230V mains will be much lower, e.g. about 6A @ 110V, so a normal PC type mains power cable is suitable.

I appreciate it. I wasn't sure if the PC cable would be good enough. Thanks.

Edited 1 time(s). Last edit at 05/01/2015 02:42PM by fatesalign.

Well everyone, for starters I wanted to say that I didn't kill myself. The power is working nicely, I'm just kind of annoyed because the motor plugs are not the correct plugs for the board, but they will work. The only problem is that the original plug only allowed it to go in one way, but this allows either way. I wanted to know if it will blow the motor if I switch it the wrong way. Thank you.

Reversing a 4 pin stepper motor connector won't do any damage provided the power is off when you do it. It will reverse the direction of rotation of the motor.

Edited 1 time(s). Last edit at 05/02/2015 03:00AM by dc42.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].