Electrical Question Regarding LPL 4500-II

[Albanese]

Hi:

I am new to the forum and please excuse my question if it is old ground. Recently, I purchased a Saunders LPL 4500-II enlarger. When it arrived, the light that was in the lamp housing did not turn on but the fan did. I replaced the bulb with a new one and the same result occurred. The enlarger was plugged into the appropriate voltage regulator. I am by far an expert when it comes to electricity. However, I was wondering the following:

1) How can I determine where the actual issue lies? My hope was that it was simply the lamp socket that would need replacing and that there is nothing wrong with the regulator. I have removed the socket and one of its lead wires is frayed and exposed which warrants replacing anyway. However, when I tested it, the socket was still working after I removed it, so I doubt it was the culprit unless it was connected loosely (did not appear to be).

2) $600+ for a new regulator or even $300 for a refurbished one especially when its component parts would be $50 at best seems rather steep particularly since I will not be using the enlarger that often. I am wondering though, if there are 250W halogen bulbs available for 120V and they emit light at 3250K and are MR16 that use the identical GY5.3 socket, why would I need a regulator at all. My understanding was that the existing fan in the lamp's housing can run off of 120V. Could I not just use an alternate set up by using a 120V bulb as opposed to the 82V? Since I am in the US, it would make life much easier as all I would need to do is connect the enlarger directly to the electronic timer which would plug into any outlet in my darkroom.

Also, does anyone have a schematic of the regulator that could help? Thanks.

[AlexSmith8]

Many models of LPL power supplys come with two "power" cords. Is your supply one of those models and do you know how to connect them properly?

If not that might be the easily solvable culprit.

The first cord is the real power supply cord and should be plugged in to a wall socket permanently. If you switch on the power supply, the fan should start to run. The second cord is the lamp switching cord. You plug it into your timer. If line voltage is present at this cord, the power supply should switch on the lamp.

The idea behind this is to protect your timer from the high power load (200 - 300 W) of the enlarger lamp.

[Albanese]

Many models of LPL power supplys come with two "power" cords. Is your supply one of those models and do you know how to connect them properly?

If not that might be the easily solvable culprit.

The first cord is the real power supply cord and should be plugged in to a wall socket permanently. If you switch on the power supply, the fan should start to run. The second cord is the lamp switching cord. You plug it into your timer. If line voltage is present at this cord, the power supply should switch on the lamp.

The idea behind this is to protect your timer from the high power load (200 - 300 W) of the enlarger lamp.

Thanks for your reply. There is a cord in the back of the regulator that is dedicated for the timer. I did plug it into the timer and the timer lit up and worked properly, but the lamp did not turn on. I am not near the enlarger right now, but is there a setting on the timer that should have turned the lamp on?

I appreciate the help.

[AlexSmith8]

There is a cord in the back of the regulator that is dedicated for the timer. I did plug it into the timer and the timer lit up and worked properly, but the lamp did not turn on. I am not near the enlarger right now, but is there a setting on the timer that should have turned the lamp on?

If this is the switching cord of the power supply, it needs to be plugged into the timers output.

The connections should be like this:

Line Voltage Outlet -> Power Cord -> Enlarger Power Supply
Line Voltage Outlet -> Timer -> Switching Cord -> Enlarger Power Supply

If correctly connected any general purpose enlarger time should work like intended. Pressing the button for the focusing light or the timed exposure switches on the line voltage output of the timer and in turn activates the lamp voltage output at the enlarger power supply.

[gth]

I had the same problem getting my LPL 4550XL going.

My power supply (PS) has a long power cord, a short power cord and a dedicated 4 pin socket.

1. Plug in the 4 pin cable/male 4 pin from the enlarger to the PS 4 pin socket.

2. Plug in the long power cord on the PS to a 120 V wall outlet

3. Plug in the short power cord on the PS to the timer outlet

4. Plug in the timer to a wall outlet and turn on the timer.

Your enlarger/PS might be set up differently.