Focomat V35 Voltage Stabilizer

[jack_pien1]

<p>Hi,<br>

Does anyone have a voltage stabilizer for the Focomat V35 where they can tell me the specs on the input and output. I'm trying to determine if my Omega C760 voltage stabilizer can be used for the V35...<br>

More generally does anyone use a general purpose UPS with an automatic voltage regulator (AVR) as a voltage stabilizer? <br>

Thanks<br>

Jack</p>

 

[mpo]

<p>If you are asking about an external stabilizer for the V35, then you can use whatever you can get, provided it is rated 100W o higher (that's the plate rating, real power of the lamp is just 75W). As the V35 is switchable between 110/240 V , you must be sure to adjust it to the proper voltage of your mains supply and regulator.<br /> I do use a 600W UPS (the smallest I found) with built in regulation circuitry and works flawlessly.<br /> The V35 column base has enough space to accommodate an internal regulator, but mine (second hand, of course) does not have one, I suspect that it may have been an option.<br /> Good luck!</p>

[colin_elliott]

<p>Indeed, a voltage stabiliser was an option for the Focomat V 35<br>

2 versions available...........Code No.17437 for 115v model and 17438 for 230v model.</p>

[jack_pien1]

<p>Hi Marcelo,</p>

<p>According to the <a href="http://www.bonavolta.ch/hobby/en/photo/v35.htm#Wiring">wiring info on bonavolta.ch</a> the voltage switch in the back is not even wired?! Is this just specific to his V35 or do you know if all V35's are the same? I guess if I'm really motivated, I can just take mine apart... but I really don't want to deal with the hassle! =)</p>

<p>Which UPS do you have? I have <a href="http://www.ultraproducts.com/applications/SearchTools/item-details.asp?EdpNo=1815470&Sku=ULT33046">this ULTRA UPS</a>, which claims it has an automatic voltage regulator but when I stick a voltmeter in the back of the UPS, the readings are definitely not regulated - only regulated when the power is but cut off...</p>

<p>Thanks<br>

Jack </p>

[mpo]

<p>Hi Jack,<br>

Certainly Mr. Bonavolta's V35 is not wired for different voltages, mine it is. As a matter of fact, the previous owner operated it at 110V and now I'm using it at 220V. As many of these devices have a long history behind, it's very likely that some of them have been refurbished (and modified) at some point.<br>

If you are not sure about the voltage setting of yours, just plug it to 110V and check the lamp brightness. If it looks dim and reddish, then its wired for 220. Better, if you have a voltmeter (a "tester") you can check the voltage at the lamp base (lamp removed) and it should read a little more than 12VAC (repeat: AC, not DC). If you find it to be wired for 220V (measured lamp voltage will be around 6VAC) but still has the original internal transformer, you can redo the wiring manually using a soldering iron (and knowing which wires to change). I have no information at hand, but if you need to do this, I can search for something.<br>

Don't do the test described above connecting the mystery enlarger to 220V. If it was adjusted to 110V, you will burn it.<br>

If you find it was already burnt, don't panic, you can easily replace the original transformer with one designed for domestic decorative halogen lamps (12V 100W would be perfect).<br>

My UPS is a BELKIN and, to be honest, I've never checked how well (bad) stabilizes the mains voltage. All I can say is that I've never noticed any inconsistency while working in the darkroom (mostly at nights, possibly voltage is more stable "after dinner").<br>

The UPS you mention is much larger than you need, unless you are connecting some other devices to it (I do: my timer, enlarging meter and safelights are also connected to the UPS). The 1000 VA model shown on that page is more than adequate. And yes, your measurements are correct, the specifications shown there state that voltage regulation (or stabilization) occurs only while operating in battery mode, not in stand-by mode.<br>

Last thing, I chose my UPS, among other things, because it has no display nor any other light, just one very tiny and dim LED that confirms operation, that's very convenient for a darkroom... (you can always cover a display, but you have already paid a premium for having it).<br>

Marcelo</p>

[jack_pien1]

<p>Hi Marcelo,</p>

<p>Thanks for the extensive response! </p>

<p>I'll check the 12v to the bulb. I'm actually in the US which is 120 volt AC - measured 114 to 124v from the wall with my voltmeter. I noticed my V35 was set at 110 volt recently (for japanese market perhaps). I'll take some reading at the bulb with the V35 set at 110 and 120-130, 220 and see what I get at the bulb pins - if volt at pin moves when set to 220 then I know my switch is wired like yours! </p>

<p>My space is small so removing the column is sort of a pain...</p>

<p>Will update with what I find...</p>

<p>Thanks<br>

Jack</p>

[jack_pien1]

<p>So took some readings at the bulb with my voltmeter.</p>

<p>When set at:<br>

110 - 14.5v<br>

120-130 - 12.5v<br>

220 - 6.5v</p>

<p>So I guess my switches are wired! =)</p>

<p>Going to try to look for a good voltage stabilizer. Thanks all for contributing to the thread.</p>

<p>Cheers<br>

Jack</p>

[david_law2]

Hi

 

Reviving an old thread.

 

It's 230v where I live in. I measured the voltage on the bulb end last night and it says 12v. So I am naturally confused

by the above. And I asked because I was using the enlarger for the first time and it blew two of my bulbs.

 

I bought this enlarger from a US buyer on ebay which comes with the older bulb. I've upgraded it w Leica original parts

to use the 13139 bulb. I've also changed the voltage setting on the enlarger to the one used here.

 

Thought I check with everyone here before I strip the enlarger for a closer check today.

 

Any thoughts? Thanks!

[mpo]

<p>Hi David,<br>

If you already measured the correct voltage (12 V at the lamp side), there's not much to say about voltages.<br>

OTOH, you already blew two of your very valuable 13139 bulbs, so my first advice would be that any further testing be made with any other common 12 V and GZ6.35 base bulb you may get at the hardware store. That said, I'd check two possible causes.<br>

First, check if the enlarger has a real copper-wound voltage transformer and not an electronic device to perform this task. If it was a traditional transformer, no further testing needed. If it was an electronic transformer, then you must get a true-RMS voltmeter and look for a way to adjust the output of this device to 12V-RMS (there are may ways to measure AC voltages, especially if the wave form is not sinusoidal, lamps care about RMS voltage). Alternatively, you can plug a test lamp and see what happens, if it survives, then voltage is probably OK.<br>

Second (an most likely), you may have a defective batch of lamps. Are both blown lamps of the same origin? Have you touched the bulbs with your bare fingers? Halogen bulbs do not like any contamination on the surface of the bulb itself, given the extremely high temperatures reached by the glass. Any trace of finger-grease on the bulb will cause a failure of the lamp (and I'm talking about the bulb that contains the filament, not the reflector). This is the reason why many specialized lamps come with a plastic glove to handle it. If your remember having touched the bulbs or they were not sealed-new, there is a very probable cause.<br>

Finally, check all the contacts, connections and wiring, bad contacts are a natural enemy of lightbulbs. </p>

 

[david_law2]

<p>Hi Marcelo<br>

Thanks for your prompt response! <br>

It's a traditional transformer.<br>

I've done some further checks on the internet and the closest I can get is this <a href="http://www.apug.org/forums/forum41/84109-leitz-focomat-v35-problem-short-help.html">http://www.apug.org/forums/forum41/84109-leitz-focomat-v35-problem-short-help.html</a> which described a faulty transformer problem.<br>

So I am going to get a new electronic transformer to test on a test lamp first. Hopefully it's just a transformer problem and not a defective batch of lamp problem. Otherwise it is going to be a headache searching for such lamps! </p>

[david_law2]

<p>Tested with one al cheapo bulb and a new 13139 bulb one a new electronic transformer. The former was still working after testing. The 13139 bulb died after 10 mins. Seems like a batch problem with the halogen bulbs. Sigh!</p>

<p>Given the fact that the 13139 bulbs are hard to source and expensive, I am thinking of alternative bulbs. Read abt the mix opinions of the Osram 64615 bulbs, so I am wondering if there are other alternatives. </p>

<p>As the v35 enlarger was terminated at least a decade ago, newer bulbs that have emerged since then would not have been tested & endorsed by Leica lab.<br>

For those who still use this workhorse in the darkroom, I think we owe it to ourselves to look at alternatives which are more affordable and readily available. Otherwise we will be in a fix when the 13139 bulbs are finally gone, much like the even earlier 6604 bulbs.</p>

<p>Bona's website listed the requirements of such bulbs, plus some search on the specifications of the 13139 bulbs show the following :</p>

<p>1)12V/75W (or 12V/100W has been documented)<br>

2) abt 15 degrees beam angle (narrow angle to pass thru opening of the diffusion box. Too wide and the a good part of the bulb's light gets blocked resulting in low light output from the enlarger's projection)<br>

3) MR16 size<br>

4) GZ6.35 base (although this can be changed by getting the right bulb socket if needed)<br>

5) 3400K color temperature<br>

6) Bulb position : Horizontal<br>

7) Heat dissipation thru the back (cold mirror)</p>

<p>I think there are a few bulbs that meet the above criteria, so will have to test them out to see how they perform.</p>