Leitz Focomat 1c US electrical compatibility?

Greetings

 

I have a serious dilemma and hope someone can help me figure it out.

I am about to purchase a late model Leitz Focomat 1c. The problem is

that I am buying it from a gentleman in the UK while I live in the

states. It just recently occurred to me that there may be an

electrical compatibility issue. I asked the seller about this but

his response really did not address the core issue. I asked if the

1c would work out of a US outlet. His response was that a 110v lamp

could be used since there is no transformer. Unless I misunderstood,

the lamp has little to do with the voltage difference and prong

compatibility.

 

My question is: does anyone know if a European model Focomat 1c is

compatible with US voltage, (220 v. 110)? Not knowing too much about

electrical mechanics myself, I called the local Home Depot and asked

one of the electrical people over there. The person I spoke to said

that I would have to have a new 220v line put in for the enlarger to

function. I then asked about a simple converter or adaptor but he

said there was no simple solution to my problem. If anyone could

shed some light on this I would be very grateful.

 

Thanks,

Mark

 

P.s. Unfortunately, even though this is a late model 1c, it does

not come with the focotar-2 lens. Instead it comes with a regular

focotar 4.5 /50mm. The owner says the lens is a late model �MK.2�.

Does anyone know what that designation means and how it differs, if

at all, from either the older focotar or later focotar-2?

The problem would be... is the lamp available for 110 volt (really 117 nominal N.A.Power Grid spec). If the lamp is available, and it has the same base as the existing lamp, then changing the plug from UK style to North America style is all you need to do. The latter part is easy, and the plug is available from any hardware store. You'll have two wires that go to the lamp, and it doesn't matter which way you connect those. There may be a ground wire, that goes to some point on the chassis (metal) of the unit. That should be wired to the ground (green screw) on the new plug. Thats it!

Actually it does matter which way you connect the wires. I am not sure what the colour scheme for British wiring is, but one wire will go to the center terminal of the lamp and the other wire will go to the screw shell of the lamp. An american plug with two prongs will have a brass screw and a silver screw. the silver screw should be connected to the wire that goes to the screw shell of the lamp. the brass screw should be connected to the wire that goes to the center terminal of the lamp. If there is a switch on the enlarger it will be connoected to this. If there are three wires one of them will be connected to the frame of the enlarger and this should be put on the green terminal if you are using a three prong plug.

Y'know, what you say makes sense, having the ring (thread of the lamp socket) connected to neutral. On a practical note, I got real curious and pulled the plugs on the living room lamps, bedroom lamp, and office lamp, and none of them have polorized plugs, so I'm wondering if its really a moot issue, since the plug can be inserted either way into the socket.

Generally the hot side in the USA is connected to the shell/threads of 120 volt ac lamps. The center contact/button is the hot side. This reduces shocks if the entire affair is wet/damp; because the almost at ground neutral wired shell is closest to the frame of the lamp. This only helps on a plugged in lamp if the cord and socket is polarized; or in a hard wired lamp that is wired correctly.<BR><BR> In the wall with 120 volts ac; the white wire is the neutral; and the black wire is the hot side. To remember this color scheme; remember in the cold western movies; the BAD guys wore Black; and the good guys wore white..The hot side plug has the shorter vertical slot. The other contact is the green wire ground; which only ties back to the neutral at the panel box buss bar. The neutral wire maybe a few volts away from ground; because of the voltage drop thru the neutral. I believe the UK doesnt use this scheme; and only uses 220 volts; with both side hot to earth/ground.<BR><BR>On our old Durst 138 5x7 enlarger; when the lamp's plug was reversed into the timer; one would get a buzz/shock from the platen when one had damp hands. This is when the shell/threads of the point light source lamp was hot; instead of at near ground/neutral voltage. Reversing the plug eliminated the shock problem. Many times during darkroom "spring cleanup" all the items in the darkroom would get moved around; and the shock problem would reappear; reversing the plug would fix the problem.

If a 110 volt bulb is difficult to find; of could buy a 100 watt travel transformer that goes from 220 to 110 volts. Green wire grounding of enlarger frames is required here for safety; because the are an electrical item in a damp area. If not grounded; a ground fault device maybe used.

The plug on my Valoy II (certainly electrically identical to your

Focomat) is NOT polarized, so I doubt if it matters how the

socket is wired. You'll just need a US style flat plug. If the

enlarger has a standard threaded (Edison base) socket, you'd

just use a normal #211, 75 W enlarging bulb. If the enlarger has

a British-type bayonet-base bulb, you could easily install a good

US porcelain socket (or if you're uncomfortable doing it yourself,

have the job done by someone who rewires lamps).

 

The solution suggested by Home Depot would also work, but it's

idiotic! After you have an electrician install a new outlet, you'd

need to find a source of 220 V enlarger bulbs AND still install a

new plur--US 220 V plugs are nothing like British or Eurpopean

ones.

Robert; If the plug is not polarized; it can fit into the wall socket both ways ( we both know that! !! )<BR><BR><b>But</b> the leakage current from the hot wire to the enlarger frame is maybe 100 times higher when the lamps shell/threads is hot; instead of a center pin.<BR><bR>Maybe the lamp has dual posts; and the leakage is the same.<BR><BR>I'm just pointing this out because I am a registered Electrical Engineer and I have also gotten shocked by enlargers in damp darkrooms!

Kelly,

 

Interesting--how can I tell if my un-polarized plug is inserted the

'right' way ( short of standing in a puddle and waiting for a

shock? Also, I ground my enlarger (with a wire from the chassis

to a cold water pipe) mainly to eliminate static electricity and

dust). Does this make it safer or less safe? (or doesn't it

matter?)

Robert; Re"Interesting--how can I tell if my un-polarized plug is inserted the 'right' way" <BR><BR>You can umplug the lamp or enlarger an connect a ohmmeter from the lamps/thread/ shell to each part of the plug. The wire that is connected to the shell should connect to the neutral. The neutral socket pin is the tallest vertical rectanglar pin on the left of the ac 120v wall plug.<BR><BR>A leakage tester connected between the enlargers frame and ground will always show a tiny tiny current leakage; which depends on the condition of the lamps socket insulation. With dampness, dirt, and old age the leakage is much greater. When the cord is reversed so the center contact is hot (instead of the threads/shell); the leakage current is way less. Green wire grounding the enlarger frame shunts this current back to ground; and protects the operator. <BR><BR>I have alot of surplus electrical gear; some that is very old. Some times the insulation is shot; or the cords have been replaced wrong; and one can get a shock. <BR><BR>Around here we have damp weather & humidity; and getting shocked is easy. Also sometimes ones house's wall plugs are wired wrong. Like reversed hot and neutral and or green wire ground not connected. Radio shack and home Depot etc have plug testers that can be used to check if ones plugs are wired up ok. Our family room and backporch circuit was found to have no green wire ground. Now I know way I got shocked once by our old electric trimming mower! The 3 wire cord doesnt help if the wall plug is bogus. <BR><BR>

I suggest you rewire the enlarger before you use it. I've owned and rewired several Focomats - very often the insulation on the wiring has rotted. Its obvious on the exposed wiring but the real problem is the wiring inside the column. When that insulation fails, you'll get a shock! When I rewire a Focomat I omit the switch under the baseboard and plug the power cord directly into the timer, there's no need for a switch when you have a timer to control the light - the timer is your switch. You can even run the cord straight from the enlarger head to the timer and skip the wiring inside the column. This is the simplest way to do it. At this point you have a lamp in a socket, a cord and a plug - pretty basic. In my opinion any older enlarger should be rewired before use, or at very least every inch of the wiring should be carefully inspected.

Mark:

 

I vote with Kelly. I have a UL listing for Industrial Control Panels as well as being an Electrical Administrator and Journeyman. We had a youth KILLED here in Alaska a few years ago because a lamp was miswired. He touched the lamp and a heating pipe. Generally miswired is not a major problem, but any time you are working near or around water, the ground path changes due to the decreased resistance induced by the water path. Take a look at the bulb and see if it has a standard type bulb, if it does, just rewire the unit. Another solution that I use is to install a GFCI (ground fault circuit interrupter) required under the later National Electrical Code in the US in the darkroom. With this, you would not have to rewire the enlarger because of polarity, but you might get some nuisance trips. I would still check out the integrity of the insulation on the enlarger.

 

Good luck.

Thank you all for the information and advice. Because I am not really comfortable with wiring and re-wiring and don�t want to take my chances with the prospect of having a big undertaking before I can begin using the enlarger, I have chosen not to buy this particular Focomat 1c. They pop up now and then, so even though this was quite a good deal despite exuberant shipping costs, I�ll wait for the next opportunity. Again, thank you all for the quick and informative advice.

Mark

"<cite>Because I am not really comfortable with wiring and re-wiring and don?t want to take my chances with the prospect of having a big undertaking before I can begin using the enlarger,</cite>"

<P>

These issues are <B>NOT</B> particular to an <em>oversees</em> Focomat or even a Focomat but are part and parcel of any older electrical appliance you may purchase anywhere.

<P>

Many of these devices were made before 3 prong wiring were widespread and do not conform, unless they have been rewired, to any current safety codes. Much of the older insulation materials too seem to not weather the test of time well. Its, however, no major undertaking to upgrade wiring. These older devices were designed to be maintained in this way. Once upon a time it was considered standard darkroom practice for people to clean, polish and paint surfaces, oil/lubricate moving parts and upgrade wires from time to time just as people maintain their other machines such as motorcars.

<P>

To the Focomat. The switches and fixtures are rated for several amps at 250v so there is NO problem using them at 110v. The power is directly to a simple Opal bulbs not very much unlike those frosted 75w or 100w found mundanely in household fixtures--- the main difference is where the model and wattage tend to get printed and, of course, the price (why many people use household bulbs with the printing scrubbed off).

<P>

"<cite>I have chosen not to buy this particular Focomat 1c. They pop up now and then, so even though this was quite a good deal despite exuberant shipping costs, I?ll wait for the next opportunity.</cite>"

<P>

The used market seems to be filled with equisite examples available for low prices that seem to be in free-fall. Zeitgeist is digital and it seems enlargers and other artefacts of "<cite>traditional photography</cite>" are being rapidly cast off to the junk yards..

Hello. If this thread is still alive, I have almost ready to use a mint Leitz Focomat 1c. The last step is to wire the unit. Can anybody help me with this issue? The photo shows the mess I discovered when I opened the black cover on the underside of the wooden base. I live in Colombia and the electric standards are the same as in USA. Thanks

EDUARDO

 

It looks like no continuity between the three cords on more than one wire.

 

As someone noted, you can bypass the switch.

 

Ignore (or cut off) the one to the switch, for the others, blue to blue and brown to brown.

 

The screw-style connectors shown are popular in Europe, and I believe legal in other countries.

 

The yellow/green should be ground, but I don't know which one goes where.

Hi Glen, thank you very much for your help. Now I find things a little more clear, but what about if I want to bring my enlarger to factory standards and use the incorporated switch? Any suggestions? Please see the attached photo I took of the circuit plan glued to the bottom of the metal cover. It seems it does't coincide with the colours of the cables. By the way, "tierra" means "ground" in Spanbuish

I have a Leitz Focomat 1C that I haven't used in years. Make me an offer for it. I'm in California. It includes a Rodenstock 2.8 lens that I think is the next best thing to a Leitz Focotar. Good luck.