Durst CLS 1840, 220 volt equipment problem

[scott palmer]

Okay, long story with, perhaps, a simple solution. Durst 8x10 with CLS1840 head and EST 1500 N, 220 volt, power source. Using a Philmore ST-3000 step-up, step-down transformer to power the EST 1500. Using a Gralab 451, 110 volt timer. The relay in the 1500 is set for a 110 volt timer. Turn the transformer and power source on and everything is wonderful. Fan works and everything seems to be ready. Turn the timer on and everything stays wonderful. Hit the timer button for an exposure and all hell rains down on the world. The transformer starts buzzing loudly and vibrating like a magic fingers bed. As it's buzzing, the lamp comes on, but does not respond to the timer settings or switching — just stays on until the power is cut at the transformer. The same thing occurs if I switch the timer to 'Focus': transformer goes nuts and lamp stays on until the power is cut. This equipment is new to me and was supposedly working as designed when I picked the unit up. All fuses in the power source read good on a continuity test. The transformer is delivering the correct voltage at the receptacle. Switched out timers and had to same problem. Everything works, just not the right way. I spoke with J.J. at Durst Oregon. He said everything is connected properly. I have a lot of experience with repairing and restoring darkroom equipment, as well as vintage audio amplifiers. But this 220 stuff is new to me. There is nothing obviously wrong with the equipment or the connections. J.J. said that his only thought was that the power source may have a problem. But shipping it all the way up there is expensive, and I do much more complicated electronics work than this could require. Unfortunately, I don't know were to start with this mixed voltage set-up. Anyone have any thoughts on the problem?

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[ic-racer]

At first I thought this was the EST 1000N, but on closer reading I see you have the EST1500N. Is the EST 1500N something unique to Durst USA, I can't seem to find a schematic for that unit.

[Ted R]

This shows some confusing symptoms but 220V AC works just like 110V just bigger. Was this made in the USA or Europe? If Europe the wire color codes are brown=live, blue=neutral, green+yellow=earth. Perhaps it would be worthwhile to open up each unit in turn and verify that the live neutral and earth connections go where they should and that there are no polarity inversions or mix ups between neutral and earth.

[ic-racer]

After some more research it seems as if the EST1500N is not a Durst Phototechnik GmbH Bolzano/Italy product. I checked the Durst-PRO USA site and can't find the schematic or repair manual for that unit. I'd contact them for more information.
The picture of EST1500N on the Durst-PRO site looks a little different than what you posted. Maybe you have a newer or older model.
http://www.durst-pro-usa.com/images/accessories/power_supply/2.jpg

[ic-racer]

This is the Durst GmbH EST1000N schemiatic but I don't think it shares anything with your unit other than the initials EST in the name.

[ic-racer]

In USA there are two common 220 hookups.

I can't say anything about the EST1500N, but the Durst EST1000N uses #2 below. Not #1. I don't know anything about running it off a transformer.

#1

http://wiringdoneright.megaweb.xyz/range/1.png
#2

http://www.tropicalsaunas.com/index_htm_files/83888.jpg

[scott palmer]

Thanks so much for the responses. The unit is manufactured in the US. I haven't been able to find a schematic either. Also, I understand that 220 is the same as 110 in theory, I just don't understand why the malfunction seems to manifest through the step-up transformer, which vibrates and buzzes loudly when the timer button is pressed for exposure, or the switch is clicked to 'Focus'. Also, I can't figure out why the lamp stays lit, even after the timer exposure has expired. That seems like it might be a problem with the relay. I'm stumped. Additionally, the focus motor won't work properly either. But that is, as far as I can tell, completely unrelated to the lamp head. It's not even on the same circuit. However, the switch continuity tests good, but I can't get any power to the motor. The motor does work. It ran a couple times, but somehow independent of the switch. It seems to be in 'Lock' mode.

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[ic-racer]

Just a thought, are you running two switching power supplies in series? Sometimes that does not work so well.

[scott palmer]

No, just the one power supply. The only other equipment in the line is the step-up transformer, which was used for years with this enlarger. It's just that something has changed during the transport process. It was only a few miles, but I still needed a trailer and had to remove the head. But the head is attached with only four bolts. Not a big deal. But by the time I unloaded the unit and reassembled everything, all these problems cropped up. With the head, it's the introduction of the timer into the circuit that causes the problem, which doesn't make any sense to me. Plus, the focus motor, a 24 volt, DC unit is a big question mark as well. I can't find a schematic for it either. It's connected to the switch with Cat 5 cable, and I don't know how it's wired. So checking the circuit is no simple matter. The switch is good, but that's about all I'm able to confirm. It's all 110v, but how it's wired is a little weird.

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[johngb]

Hi Scott,
I just signed up and noticed your post about the power supply. I hope that everything has been resolved at this late date but just wanted to mention something.
When I first got my 1840 I was using a step-up transformer that could not handle the wattage. I returned it for a 3000W transformer and it stayed cool and quiet.
As for the lamp not turning off.......it's not supposed to! The head is designed so that the lamp is always on and at the right color temperature when the exposure is made.
That's why the enlarger has a solenoid-actuated shutter to block the light from the constantly burning bulb. I did not love the idea of a 1000W bulb burning all the time so I switched it out for a 500W version (EHD I think.) After that I realized that I might not have needed the bigger transformer after all.
I know that this is probably too late to be of assistance to you but perhaps someone else has similar concerns.
Johngb

[ic-racer]

If the lamp on a CLS1840 is illuminated all the time there is a big problem. The lamp should only have a low voltage (15V) to keep it warm between exposures, it should not illuminate until the second before the shutter opens and for a second after the shutter closes.

[Leigh]

Thanks so much for the responses. The unit is manufactured in the US. I haven't been able to find a schematic either. Also, I understand that 220 is the same as 110 in theory, I just don't understand why the malfunction seems to manifest through the step-up transformer, which vibrates and buzzes loudly when the timer button is pressed for exposure, or the switch is clicked to 'Focus'.
Those symptoms indicate that you're drawing much too much current from the step-down transformer than it's designed to provide.

You need to get a new transformer, and NOT a Philmore (imported junk).

- Leigh

[johngb]

Thanks, that makes a lot of sense and indicates that mine was malfunctioning too. I'm glad that you caught my misinformation before it did any harm.

[Leigh]

Sizing the step-up/-down transformer properly for the load is a simple matter. Look at the nameplates for each item that plugs into the transformer and write down the power consumption (probably in watts). Add all those values together, then multiply by 1.2 or so to give a safety margin.

The transformer should be rated at least that value, or higher. Transformers are often rated in Volt-Amperes (VA). To a first approximation, VA = watts, so 1500 VA = 1500 watts, etc.

Also, you might encounter either value with a k (kilo) prefix, meaning 1000. So 1.5kVA = 1500 VA.

- Leigh

[scott palmer]

Hi Scott,
I just signed up and noticed your post about the power supply. I hope that everything has been resolved at this late date but just wanted to mention something.
When I first got my 1840 I was using a step-up transformer that could not handle the wattage. I returned it for a 3000W transformer and it stayed cool and quiet.
As for the lamp not turning off.......it's not supposed to! The head is designed so that the lamp is always on and at the right color temperature when the exposure is made.
That's why the enlarger has a solenoid-actuated shutter to block the light from the constantly burning bulb. I did not love the idea of a 1000W bulb burning all the time so I switched it out for a 500W version (EHD I think.) After that I realized that I might not have needed the bigger transformer after all.
I know that this is probably too late to be of assistance to you but perhaps someone else has similar concerns.
Johngb

johngb: Okay, I'm now able to get back to the 1840 difficulties. In re-reading your response, I'm confused. Unless I'm overlooking something, my 1840 does not have a shutter mechanism. Additionally, I know that Jen Jensen passed away, and that Durst USA no longer exists. The problem there is that he produced the EST 1500N power supply and now there isn't any information about the product. However, the unit is still giving me problems that I've been unable to diagnose. It powers up the bulb, but it (the bulb) stays on all the time the power supply is turned on. Additionally, the Gralab timer I'm using doesn't seem to have any effect, in any mode. I guess I'm really back where I started from. Any suggestions?

[scott palmer]

If the lamp on a CLS1840 is illuminated all the time there is a big problem. The lamp should only have a low voltage (15V) to keep it warm between exposures, it should not illuminate until the second before the shutter opens and for a second after the shutter closes.

Update. Okay, I'm making progress. The timer was bad and always stayed in Focus. So different timer and things are almost okay. The problem now is, once the time for the exposure is complete and the timer resets itself, the bulb stays of for around 10 more seconds. The fan comes on as soon as the exposure begins and stays on for a while after the exposure, and after the bulb has finally gone out. I assume the fan is running on a thermostat and shuts off once the bulb temperature drops far enough. But the bulb stays on at apparent full strength for that 10 further seconds. Is there supposed to be a shutter mechanism with this thing? If there is, I can't find where it goes, much less where it is.

[ic-racer]

The EST1000 runs the bulb just for a second or so after the shutter closes. Your ten second delay is probably adjustable in the unit somewhere, but I'd be happy at this point, seems like most of it is functional at this time from your description. Maybe the 4 black boxes with adjustment knobs, those could be the timers that run the relay bank.
From what I recall on the CLS1840, the 1000W lamp is 120V the blower [Lufter] is 220V, the shutter motor is 24V, the shutter motor relay coil is 24V and the indicator lamps are also 24V.
The shutter CLS1840 shutter should be visible by removing the upper diffusion box [Oben]:

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[scott palmer]

Problems solved. Turns out, the large cable that connects the light head and the power supply had been damaged at some point, somehow. I was running out of ideas, so I finally checked the continuity of all the cables and found one wire that, when I opened the connector, had a broken solder joint. It was obviously one of the wires to the shutter. It was also flopping around inside the connector body and shorting out other connections every time the cable was moved. I soldered it back together and everything works fine. I think I finally understand how and why this unit works as it does. It seems that the timer signals the power supply which then applies power to the bulb. But the shutter doesn't open until the bulb is up to full color temperature, which takes a second or two. So there's a delay. But once the shutter opens, it stays open for the period the timer indicated, just not synchronized. The bulb stays lit after the timer has expired, because it opens after the timer is started. So it was simply staying lit for the indicated time interval. It also stays lit after the shutter closes, so as not have an uneven exposure as the bulb powers off, which takes a couple seconds, with the color temperature slowly dropping. It doesn't just shut off instantly, in terms of light generation, as does a traditional enlarger light source. At least I think that's right. If it isn't, let me know. And thanks to those who weighed in on my post.

[newvisionphoto]

EST1000N Schematic needed for doing a repair.I forgot to give you my email address. It is overmoen@gmail.com
Sincerely with thanks, Jay Overmoen

[atram_r]

This is the Durst GmbH EST1000N schemiatic but I don't think it shares anything with your unit other than the initials EST in the name.

Hi! May I ask you to send me a bigger image of the schematic? I need it to repair my unit.
Thank you a lot!

[ic-racer]

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[atram_r]

I can't open it. Could you please send it to me by email?
marta.rizzato@gmail.com

Thank you a lot!

[ic-racer]

Ok check your mail.

[YvonneClarkson]

Well, just like Ted R said above, this is all showing some really awkward, or even confusing symptoms, as the 220V AC works just like 110V, the only difference is that the 220v ac is way bigger. And to be honest, I have been really surprised when I found out that EST1500N is not a Durst Phototechnik GmbH Bolzano/Italy product, I was sure that it is a dust phototechnik, as I also had one. By the way guys, don't you experience power outages because of it? I was having a very bad electricity plan back in the day, and in addition with this thing, I was experiencing power outages almost every second day. Thankfully, I have found a great review on Simply Switch (https://www.simplyswitch.com/energy/guides/what-is-a-letter-of-authority/), and it convinced me to change the electricity plan.