Forum - Banjo Ben Clark

Dichroic halogen lamps

#1

A question I hope one of you can maybe help me with.
I am doing some experimenting with lighting in the cave. :bulb: :bulb: :bulb: Our mains power is 110v, like the US, as the regulations for underground installations were mining regs and therefore 110v - and of course not available in Oz!
I have been trying out dichroic halogen 50w lamps. The usual common dichroics are 12volt with a MR16 base -two pins that just push into the lampholder. These require a 110v - 12v transformer.
I am trying to source dichroic light globes with a GU10 base. The GU10 is a different system with two thicker terminals with a wider bit on the end - you push and turn it into the holder to lock it in. The advantage is that this kind is already mains power and does not require a transformer. Here they are 240v, in the US would be 110v.

I have found a manufacturer in China who makes 110v GU10 dichroics but they only supply in quantities of 1000 :mrgreen: As I just want to do some trials at this point I just want to get hold of a dozen or so.
They must supply them to someone but I have looked on the net and can’t find anyone in the US who retails them.
Can you buy them off the shelf there, either in supermarkets or hardware stores?

Here are some urls to show you what I am talking about.
This is the 12v one:
http://hntangming.en.made-in-china.com/product/CoImjeycSuWq/China-Halogen-Lamp-MR16-.html

Here is the 110v one I am looking for:

Here’s a better picture of the GU10 base:

Just thought you had maybe seen these or could check next time you are in a big hardware place with a reasonable light selection.
Would greatly appreciate any feedback.

By the way, before anyone says it, I have tried out some LEDs (5w warms and whites) :bulb: but the colour rendition is really cold and unfriendly, I’m after a warmer look.

#2

The bases don’t look familiar. But I did a google search and it looks like walmart online has a five pack for $16.54.
walmart.com/ip/15040854?wmls … la&veh=sem
They are out of stock, but that seems helpful nonetheless. It says they are in stock locally. If I find some local, what’s the cheapest way to ship from here to Oz? On the flip side, if you want to come over to get some, you are welcome to stay here :slight_smile:

I did an amazon search and it looks like some are available. Same basic price range.
amazon.com/s/ref=nb_sb_noss_ … words=gu10

#3

Thanks for that Mike. From your leads I’ve done some further searching and realised that they are not online as 110v but as 120v! I can always now order some samples from amazon if I can’t find another manufacturer who will do small quantities for me to trial.
I also had a long meet yesterday with a relly who by pure chance has worked on cave lighting design and we nutted through a few approaches. Although he has done a few complete cave jobs using LEDs he agrees that they do not have good colour rendering and that the technology is still not well enough developed to be totally reliable. He thinks my approach with dichroics is the best and most cost effective for now and that they can always be replaced further down the line with LEDs. He also explained that 35w high efficiency globes have almost the same output as 50w standards - I may have to go with them as the Oz govt is restricting importation of what they regard as low efficiency lamps to lower domestic power consumption. Apparently Australia is the highest world user of dichroics so they are pushing LED replacements.
I’ve also designed and built a prototype lampholder from 2" stainless tube which I got my exhaust guy to expand at the end to take the diameter of the globe. I reckon I can build a hundred or so fairly cheaply myself and come up with a very cost effective lighting revamp.
Thanks also for the invite - I’ll have to see if my boss will allow the trip but I suspect not - lawns to mow, water to pump, building to do etc :frowning: