Halide question

[MikMcgyver]

Can you put smaller bulbs in a bigger rated socket? like 150w or 175w in a 250w socket or are they different sizes? Thinking about going a different way with my lights and was just curious as I have never actually looked at a MH fixture..

[yote]

I dont think it would be safe.
I'm pretty sure your bulb life would be cut in half.

[bobby]

The socket size is the same for all the bulbs, but there are different size bases and different size sockets you will need to figuer what you have the but the bulb in what ever watts you want with the right size base. The most common is the E 39 base but if you buy a E40 base you can put both 39 and E40 bulbs init but not vice versa.

[hotimportknight]

Also, you wouldnt want to run a smaller rated bulb in something that is generating 250 watts, that would burn it out rather quickly, if not dangerously. You could put a bigger bulb in a smaller rated fixture, it just wouldnt be as bright as it would be if it was in a fixture rated for the bulbs maximum.

[bjohanson1234]

I am going to have to disagree with import.

Putting a bigger bulb on a smaller ballast would be bad. The bulb would try to draw enough current to illuminate and over load the ballast or just not start up period. DONT DO IT!!! Things have ratings for a reason. Use a 250 Watt ballast with a 250 watt bulb. Please do not fool around with electricity if you do not know what you are doing. It will hurt you.

Brian

[hotimportknight]

You think so? Someone on the forum was an electrician, but I dont remmeber who, was that you bjohanson? If that is you then I would trust you for sure on what your saying, but from experience in car audio and 12v crap, im pretty sure you could put in a bigger bulb as long as the impedance is the same. All a bulb is, is an open extension of metal under vacuum in an inert gas filled tube, it doesnt draw power really, it just makes a contact for 2 points to flow through... So going smaller rated would mean there is too much flow going through the bulb, which would burn it out. a higher rated bulb would allow for the max flow from the ballast and just not provide the optimum max flow of current to light the bulb.
I've never learned about it, or taken a class, so if i'm wrong dont be offended or anything, I just taught my self as needed as I worked on cars for the last 5 years. So someone please chime in and let me know if my theory is wrong, or right, I'm always willing to learn from someone who knows what they are actually talking about...

[bjohanson1234]

In electricity, the ballast would be considered the source of the power. The bulb is the load. The load draws current from the source. It will draw as much current it needs to opperate. So if the source can not supply enough current, the bulb will not opperate or draw so much current that the source would over load.

Also, MH bulbs are not like normal incandecent bulbs. They dont have a metal filiment. They are considered a gas discharge light. The gas gets energized and becomes the path for the electricity. Thus giving off light in the process. If the ballast cant supply enough current to get the initial spark to ignite the gas, it wont operate.

Metal halide lamp - Wikipedia, the free encyclopedia

Here is a nice little article on MH

Now the case that you gave me, you are probably refering to the voltage rating of the bulb. A 12V bulb on a 6V supply would be half as bright and would burn out on a 24V system. This is because the current being drawn by the bulb decreases on the 6v system and increases on the 24v system.

The equation you use to show this is Volts / Resistance = Current

Say the bulb has a resistance of 1 Ohm
In the 12v system, the bulb would draw 12 Amps
12V/1 Ohm = 12 A

In the 6v system, it would draw 6A
6V/1 Ohm = 6 A

In the 24v system, it would draw 24A
24V/1 Ohm = 24 A

Since the bulb was only designed to be on a 12V system, it is only designed to draw 12 amps. So when 24 amps are going through it, it will burn out.

Hope I didnt confuse you

Brian

[Bifferwine]

You are good.

[yote]

We've gone from reef lighting to ohms law.

[bjohanson1234]

Sorry I couldnt make it dirty for you guys

I have always been of the thinking to not just give an answer but also an explination of your answer that way people will know why you are thinking the way you are thinking

Brian