wiring question for enlarger

[lesd]

Through a friend, I have just rescued a Durst 67 colour enlarger from imminent disposal. I am attempting to wire the cable to a female connector which plugs into my timer. However, the wires are black and white not blue and brown like they usually are here in the UK.

I wonder which goes in the neutral and which goes in the live connection? I thought I should seek advice as I do value my life. I understand that in the USA white is neutral and black is 'hot' (live) but I would be surprised if the enlarger had US wiring as it would have been bought in the UK.

Any suggestions most welcome.

Les

 

[Erik L]

White is normally neutral and black is hot as you mention for the US. Maybe it was wired for sale in the US or was was rewired somewhere along the way?
good luck
Erik

 

[Monophoto]

I'm not familiar with this enlarger. What kind of bulb does it use? What is the voltage rating of the bulb?

As a practical matter, most low voltage wiring uis actually rated at 600v. can be used interchangeably at 120V (the US standard) and at 240v. (for the Brits). So I would be more concerned that the bulb is correctly rated for application.

 

[bdial]

The bulb is probably not mains voltage. Is the cord you are working with from a power supply box, or directly to the enlarger?

 

[lesd]

It goes directly to the enlarger

 

[RH Designs]

As it's a colour enlarger, it will almost certainly use a low voltage halogen lamp so you'll need a transformer. So don't plug it into the mains just yet! Can you find a voltage/power rating on the lamp?

 

[lesd]

No idea about the lamp. I guess I will have to undo some screws and find out.

A transformer? This sounds daunting. My electrical expertise stops at wiring a plug!

Les

 

[lesd]

I have read a bit and now understand.! I wonder why there was not a transformer with it? I will find out what sort of bulb I have got and take it from there.

Thanks

Les

 

[lesd]

It seems odd to keep replying to my own thread but I have found some specifications on a JOBO website:

Color head
Light source M 670 Color M 670 VC
Selected halogen lamp 100W/12V (Colamp 100 S)
Power supply 115V to TRA 305 Transformer or EST 305 Voltage Stabilizer
Illumination Via mixing boxes
Filters Dichroic filters (Yellow, Magenta, and Cyan) Dichroic filters (Yellow, and Magenta)
Maximum filter density 1.7 (170cc)

So it looks like I need a step-down transformer. I wonder if this would be inside the enlarger head or would I need to obtain one seperately?

Les

 

[Ian Grant]

The lamp will be 12v or possibly 24v. If 12v a transformer designed to run multipe 12v shop fitting halogen lamps may well be ideal, they are heavy duty often with built in fused protection. Usually colour enlarger transformers have some type of built in stabilisation.

The transformers were always external, usually switch-able between 115 & 230V (240).

Ian

 

[RH Designs]

So it looks like I need a step-down transformer. I wonder if this would be inside the enlarger head or would I need to obtain one seperately?

Les

Separately I imagine. As Ian suggests, a low voltage lighting transformer would probably work - I use one on my LPL 7700 which also uses a 12v/100W lamp.

Maplin sell Dead Link Removed (choose the 105VA version) which looks like the one I use. It has a stabiliser built-in too and will be much cheaper than the dedicated Durst model.

 

[haris]

Does it matter with AC?

I don't know for USA or UK, but if you use standard European connector (as for example used in Germany), you can plug it in wall outlet in 180 degrees turns, and there is no mention on connectors which is live and which is neutral pin. That means it is no matter which wire is neutral and which is live. What DOES matter is third wire (and connector's pin), and that is ground. You really don't want ground wire to go into live wall outlet. As ground wire is usually connected to body of electric aparatus, and enlargers usually have metall body, you know what I mean...

Ground wire in Europe is 2coloured, yellow (gold) and red if I remember correctly (yellow is for sure one colour, second I can't remember, but never mind, it is only 2coloured wire for 1phased electric wiring), neutral is one coloured and if I am right it is brown, and live is also one coloured, blue.

That means, you don't have to wory will you mix neutral and live wires, but you MUST connect ground wire to appropriate connection place. If you fail to do that, you can be dead when you touch your enlarger!!!! You MUST NOT make mistake and replace ground connection with neutral and especially live connection!!!!! You can for example not to connect ground wire, and aparatus will work. Ground wire is for protection, not for function of aparatus, for function of aparatus, live and neutral are enough. But, again, if you connect ground wire on place of live wire, you will be most likely DEAD!

So, if you are not sure what to do, let authorized electrician to do electric job!

 

[haris]

For transformer, as Ian and Richard already told, try standard lighting transformer for house lights 12V/100W halogen lamps. Better to buy stabilized. Last time when I looked (few years ago), new Durst stabilized transformer costed 200 Euros, and stabilized lighting transformer here cost about 30 Euros. 170 Euros is too expencive for "Photo" and "Durst" letters...

 

[Steve Smith]

Ground wire in Europe is 2coloured, yellow (gold) and red if I remember correctly (yellow is for sure one colour, second I can't remember.

Green and yellow in UK.

neutral is one coloured and if I am right it is brown, and live is also one coloured, blue.

Brown (Red in old equipment) = Live
Blue (Black in old equipment) = Neutral


Steve.

 

[haris]

Thank you Ian, yes, I was wrong, your colour scheme is correct.

Same colours are on continent, only connectors are different.

 

[RH Designs]

Does it matter with AC?

I don't know for USA or UK, but if you use standard European connector (as for example used in Germany), you can plug it in wall outlet in 180 degrees turns, and there is no mention on connectors which is live and which is neutral pin. That means it is no matter which wire is neutral and which is live.

Haris - you're right that it shouldn't matter which is line and which is neutral for AC, except that here in the UK the neutral connection is grounded at the power station meaning that the voltage between neutral and ground is much lower than that between line and ground. For properly designed and insulated equipment (i.e. anything made recently) it won't make any difference, but for elderly equipment there may be a difference in insulation between line and neutral.

So, if you are not sure what to do, let authorized electrician to do electric job!

Agreed 110% !

 

[Nicholas Lindan]

the neutral connection is grounded at the power station

The neutral-ground connection is also made at the 'Pole Pig' - the transformer on the utility pole - and at the house. There is a ground spike at the utility pole and the house connection is either a ground spike or a strap to the water pipe.

Fusing and power switching is done on only the hot-side. If hot and neutral are reversed then the internal wiring will be hot with the power off and the fuse will be ineffective if there is a short circuit to ground. The neutral line isn't fused because you always want the hot-side to disconnect in the case of a fault. Breakers are ganged to disconnect both sides in the case of a fault on either line, as a ground fault protectors.

Some countries use a balanced 220V system, where both lines are hot with respect to ground. 220V wiring the in the US works this way. In this case both sides are fused and must be switched.

Needless to say, half the houses and half the electrical appliances are wired backwards. You can get a small plug with 3 leds that will indicate if the power is wired correctly.

The best protection in a darkroom, or any room where there is water access, is to use a ground-fault protector.

 

[lesd]

Thanks for all your information. I doubt that I could get hold of an electrician to do a tiny job like this.

As I read things I need to buy the lighting transformer that Richard (RH designs) suggested. There is a Maplin store close to where I work. I still have the cable with the white and black leads to worry about but it looks as if it probably does not matter which is connected to neutral as it is all relatively new kit.

Les

 

[haris]

Richard, thanks for info.

That is why I wrote I don't know for UK, I have only experience here in Bosnia.

 

[haris]

Thanks for all your information. I doubt that I could get hold of an electrician to do a tiny job like this.

...I still have the cable with the white and black leads to worry about but it looks as if it probably does not matter which is connected to neutral as it is all relatively new kit.

Les

If I was you, I would search for electrician. There must be someone who will do such small job. After all, you will pay for work, so it could be nice money for small work for them...

Is there any repairman who repairs old TVs, VCRs, washing machines, tape recorders, electric heaters, etc... or electric installation people. They will know what to do.

 

[Chan Tran]

If the bulb is 12V/100W lamp I would find a 12VDC regulated power supply with a 10 or 15A rating. This way I would have a very stable voltage to the lamp and such a power supply isn't very expensive.

 

[lesd]

I found a technician where I work who wired it all up for me. Great guy! Now I have a lovely enlarger to play with.

Les