Durst CLS 1840 - Need help and advice :) New Darkroom build.

[reneboehmer]

One thing I see different is that in my CLS2000, the lamp pre-warm does not eminate any light.

Oh ok, this might be because my PWM dimmer values are not accurate yet. Its just a random low voltage value atm.

 

[koraks]

Oh ok, this might be because my PWM dimmer values are not accurate yet. Its just a random low voltage value atm.

Makes sense. I'd dim it down until it just ceases to glow.

 

[gary mulder]

One thing I see different is that in my CLS2000, the lamp pre-warm does not eminate any light.

Are you able to measure the temperature of the pre-warmed bulb ?

 

[reneboehmer]

Makes sense. I'd dim it down until it just ceases to glow.

Yes, will do this asap.

 

[ic-racer]

Are you able to measure the temperature of the pre-warmed bulb ?

I don't know. I could measure the temp of the lamp base after it has been idling a while to see if it gets any warmer.

 

[Klaus Mähring]

Fascinating build, respect!

 

[Thodoris Tzalavras]

One thing I see different is that in my CLS2000, the lamp pre-warm does not eminate any light.

When my EST2000 was still working, the lamp at pre-warm in my CLS2000 was actually emitting a very-very faint glow:

 

[gary mulder]

Maybe it’s best to use the output voltage value stated in the manual for the preliminary heating.

 

[ic-racer]

I’ll check mine in dim light

 

[reneboehmer]

Small update, I changed my fan back to an SSR solid state relay again as @gary mulder suggested. The supply works fine and I have faced little issues. The only thing I had issues with was that i tested my setup with 230V lamp and the internal resistance of a 120V lamp is slightly lower than the one in a 230v lamp. I had to adjust the code until the dimming / resistor relationship was so that no more than 10 amps would flow. Theoretically the 10 amps plus would only flow for a small amount of time but, as Gary Mulder mentioned before, the Kemo dimmer trips at 10amp. I am currently facing no issues that would require closed loop voltage stabilization. I also configured my fan to run all the time. My lamp is now at the idle voltage Durst recommended in their manual. Its glowing slightly.
Thanks again to all who have helped me!

 

[reneboehmer]

Oh and I have made this small video showing oft the timer unit I build for the Power supply: https://www.youtube.com/watch?v=6FF_jPX3ewA

 

[reneboehmer]

Fascinating build, respect!

Hey, I overlooked this! Thanks, Klaus.

 

[reneboehmer]

I measured the shutter accuracy of my shutter today. The shutter itself is very accurate, but I noticed that he at the beginning of the exposure the lamp hasn't yet reached full output after 3 second ramp-up before opening the shutter. 1.5s - 2s ramp-up will give a cleaner exposure. But maybe I should just ramp it up faster with the KEMO dimmer.

The phone app I used to check this is called phyphox, it is very nice.