LPL C7700 Issue

[jaestorer]

Hello all,

I'm a bit puzzled, as last week when printing - my enlarger (LPL C7700 Pro, Dichroic colour head) just cut out and didn't turn on. I took the bulb out, as it appeared blown.

I've replaced the bulb with the one that was in there for 4 years previously, but it is now not lighting up. I have checked the fuse on the transformer and this is fine, I hear the 'click' from the transformer when you put the light on - but I am not getting any light


The filter lights are all illuminated and without issue. Really puzzled right now and searching for answers, but I'm not electrically minded lol

Thank you

Edit: to put what head is in

 

[MattKing]

Welcome to Photrio.
Which light source are you using - the dichroic colour head or the dichroic VCCE head?
On the VCCE head I have, If the filter lights are illuminated, than the bulb is on - there are no separate bulbs for them, just a small cutout in the diffusion box that diverts light there way.
Is there any chance that you put a protective lens cap on the lens before switching the bulb, and forgot to remove it?

 

[koraks]

Also a warm welcome from my end!
In addition to what Matt says above, please verify that the bulb socket is free of corrosion and the wiring between the transformer/timer and the bulb socket is OK. It's common on enlargers to run into corroded contacts on bulb sockets, requiring cleaning or replacement.

 

[jaestorer]

Welcome to Photrio.
Which light source are you using - the dichroic colour head or the dichroic VCCE head?
On the VCCE head I have, If the filter lights are illuminated, than the bulb is on - there are no separate bulbs for them, just a small cutout in the diffusion box that diverts light there way.
Is there any chance that you put a protective lens cap on the lens before switching the bulb, and forgot to remove it?

Firstly, thank you Matt!
Sorry, I forgot to add that. I'm using the Dichroic colour head. No protective lens cap over the lens - I put a bin bag over to protect from dust haha

Also a warm welcome from my end!
In addition to what Matt says above, please verify that the bulb socket is free of corrosion and the wiring between the transformer/timer and the bulb socket is OK. It's common on enlargers to run into corroded contacts on bulb sockets, requiring cleaning or replacement.

Thank you Koraks!
Yes, there doesn't appear to be any corrosion, everything is plugged in tight and clean - I am so puzzled!

Both, please see a video of what's happening -Turning on/off + bulb plug

 

[jaestorer]

Just to add -

• Fuse in transformer is fine and not blown
• Fuse in Analyser Pro timer appears fine
• Bulb socket doesn't appear coroded or loose
• All sockets are in nice and tight and clean

 

[MattKing]

Those socket connectors are prone to failure, and many have replaced them.

 

[jaestorer]

Those socket connectors are prone to failure, and many have replaced them.

Hi Matt,


That is really handy to know! Thank you.

Do you have any recommendations of where I could pick up such a spare part? I’m based in the UK, but more than happy to have a bash at it. I am searching ‘socket connector LPL’ but having no luck, I’ve even looked at The Imaging Warehouse in CA but that’s been no luck.

Thinking it’s possibly a cannabilism job?

Thank you so much! I really appreciate it

 

[Melvin J Bramley]

Hi Matt,


That is really handy to know! Thank you.

Do you have any recommendations of where I could pick up such a spare part? I’m based in the UK, but more than happy to have a bash at it. I am searching ‘socket connector LPL’ but having no luck, I’ve even looked at The Imaging Warehouse in CA but that’s been no luck.

Thinking it’s possibly a cannabilism job?

Thank you so much! I really appreciate it

I had a similar problem with a Durst M605 which has a similar bulb fitting to the LPL.
I purchased bulb holders from Amazon .
Just search MR16 bulb holder.
They are inexpensive.

 

[jaestorer]

I had a similar problem with a Durst M605 which has a similar bulb fitting to the LPL.
I purchased bulb holders from Amazon .
Just search MR16 bulb holder.
They are inexpensive.

Hi Melvin,

Thank you so much for that insight, I’ve just purchased one so hopefully that fixes the problem - thank you!

 

[torleif]

Hi, a little late maybe, but with a voltmeter/multimeter you will be able to identify the nearest point in the circuit with voltage present if you start searching from the lamp holder ´moving´ towards the transformer.