Retro-fitting FX projector with an HID lamp

[Pete Alcock]

Slightly strange one here...

 

I read with interest in the latest CPC flyer that iSolution(?) market an HID150 discharge lamp. Apparently its the same size as an ELC 250 lamp, but is brighter, lasts ages and is only £40. (ELC lamps in my experence last minutes). CPC product code DP2940747.

 

Now I have a few water fx projectors that I'm interested to see if I can upgrade to use these lamps (don't laugh).

 

I read somewhere that HID lamps run off about 80V and need a series ballast and an ignitor to get the thing to strike. Does anybody have an outline schematic or know roughly how these things work.

 

It might be a waste of time, but there is a significant upside (less heat, more light) that is intriguing.

 

Thanks,

 

Pete.

[Tomo]

A few issues to be aware of:

 

HID lamps need a ballast (electronic or magnetic).

Most ballasts cannot be dimmed - although there are a few electronic ballasts that can be, in a similar manner to florry ballasts.

HID lamps use a high voltage to strike, which is usually around 200-300V although it can be much higher.

 

Ballasts are generally specific to the lamp/lamp family as the running and striking voltages often vary considerably, even within the same wattage and manufacturer.

 

In short - such a retrofit may be possible, but the lamp burner assembly will almost certainly need replacing with a suitable HID one.

 

But don't build your own ballast - there are quite a few commercially available.

Philips do a few - this one shows a rough schematic of how they are built.

[musht]

ELC 250 an MR 16 size reflector 51mm diameter to lip, actual lamp may be less than 150W but small arc size means efficient light collection, and shorter life usually. Picture of an Osram 150W HID with bigger reflector, Marc 350 beside it was used in VL1

 

http://www.lamptech.co.uk/MEI%20Special.htm

 

HID headlamps similar idea :

 

http://members.misty.com/don/d2.html part of http://members.misty.com/don/ goes into some of the practical things about discharge sources.

 

Seen MR16 low wattage ballast and lamp combinations on ebay within recent times, Chinese origin 1p + £59.95 P&P. Vaguley remember something about some Chinese minature HIDs lacking an ingredient on the electrode coatings, big lamp makers actually do R&D, which led to life and arc stability problems on the wee ones 10-20W size. These would not look brighter than an ELC anyway though...