Electrical folks - Lighting two 175 SE MH bulbs with one 400 watt ballast ?

dppitone

In Memoriam
Is it possible to fire up two 175 watt SE bulbs with one (1) 400 MH ballast?
(Of course after splitting the wiring out to connect up two mogul bases.)
Thx !! Dave
 
How long will you want them to burn after they fire up? If they last a few seconds or hours is that ok, as long as they fire up? Is this a science project or are you wanting to use this over your tank? If you do this, be sure and video it, MH bulbs can be spectacular when they rupture and send shards of glass out. If the goal is to have a properly functioning pair of 175 watt bulbs then use a pair of 175 watt ballasts.
 
Hey Sirreal63,
You don't have to be a wise-*** about this - do you? I'm asking in reference to ballasts that we use in our house to run 12 volt lighting fixtures. One ballast can run multiple fixtures and the wattage doesn't have to be exact. The same can be done with VHO ballasts, running multiple bulbs. When you say regarding my question that doing so will blow up the bulbs or that they won't last for more than a few minutes, are you basing that on direct knowledge on the electrical components and how they work. I don't appreciate the snarky "science experiment" remark. If your going to respond to a thread, please do so with respect and an intelligent well -supported comment. Now I put it back to you to do as much, if you can.

It's just some members that spoil the bunch.
 
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You didn't really say what you were doing, people do all kinds of strange things. Your rely to Alton was about if they will fire up, not run properly and safely. They may indeed fire up but no hard facts about how long they will run, and with such a large wattage influx a rupture would likely be the case, and they can be spectacular.

Had you included the information about low voltage lighting it would have been easier to discern what your intentions were. Low voltage lights still have a wattage limit.
 
Alton said "No you can't." I didn't know if he was giving expert advice or an uninformed opinion, so I was trying to draw more information so I could understand the content better, trying to learn something. That's why I asked.

My intention was to see if I could work with what i have available - a 400 watt ballast, two reflectors with bases, and a couple of 175 watt SE bulbs - to put over a 125g FOWLR I'm starting to build.
 
Alton knows his stuff but the question could be answered with a yes or no. In short you can't run 175 watt bulbs off a 400 watt ballast, there is no multiplier effect with bulbs, they operate differently than 24v lighting.
 
It'd be cool if they could be designed to work like an icecap VHO ballast, able to run more or fewer bulbs off of one ballast just by wiring the sequence to specification.
 
I think it would be great but it won't happen. The way a HID light works makes it very improbably. There are certain things that are possible but no one would want to pay the price to have it. The most we will have are ballasts that are capable of running at multiple wattages, these are all electronic ballasts. HID bulbs/ballasts are not overly complicated, but they have requirements for starting and running that are significantly more complicated than household style lighting. If you would like to learn a little more, this is one of the best articles I have read, it explains a lot.
http://reefkeeping.com/issues/2007-03/sj/index.php
 
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