DIY Lighting Electronics Questions.

[Ra'anan]

Hey there, I started a thread the other day about a 70W ballast and heres another one along those lines.

I can get a 'complete' 70W ballast for $35 at one shop, and i'm not talking about that one...

now:

I can get a 40-700W Ignitor for $5 ... thats an ignitor for lights up to 700W which looks like this :



then I can get a 70W Ballast for $10 which looks something like this:



as you can figure, i'm missing a tansformer and hence my question...

what kind of transformer would I need to connect a universal Ignitor up to 700W to a ballast up to 600W...

with rates like these I reckon I can cheaply build a 600W ballast...

anyone know about the transformer I'd need?

and if its possible for me to buy a ballast that exceeds the capability of the lamp and still work?

 

[forthe$$69]

a ballast is a type of transformer

typically u don't need an ignitor for a 70w hps or MH
so the ballast you mentioned should work
only when you start using HID lamps over 150w do you need a transformer, ingnitor, and capacitor.
Of course i have never encountered a digital HID ballast setup.

 

[zvuv]

I've never wired up a 70W HPS ballast, but the one I have does have an ignitor. With a magnetic ballast, the ballast and transformer are the same thing.

Digital ballasts are comparatively new. I have no experience with them.

This is what I am used to

 

[Ra'anan]

a ballast is a type of transformer

typically u don't need an ignitor for a 70w hps or MH
so the ballast you mentioned should work
only when you start using HID lamps over 150w do you need a transformer, ingnitor, and capacitor.
Of course i have never encountered a digital HID ballast setup.

Gut this :



with this:



using the power switch on the psu?

 

[Nitro1990]

yes use the power switch but make sure there is no wires next to the transformer as the wires may melt and kudos for building from scratch

 

[zvuv]

Yes, you can use any switch rated for 120V and more than 2A.

BTW if you like to fool around with electronics, an old PC pwr supply can be a good workbench supply.

 

[Ra'anan]

Yes, you can use any switch rated for 120V and more than 2A.

BTW if you like to fool around with electronics, an old PC pwr supply can be a good workbench supply.

Is the transformer on the power supply itself good?, you can get PSU's up to 600W, would that mean that the transformers can be conbined or even replaced? I mean, a 250W PSU could do a 250W hps lamp if I understand correctly...

 

[Nitro1990]

i would never use a pc power supply for a hps light

no a pc power supply wont fire a hps light as there is no capacitor/igniter to fire the bulb so it will not work

 

[Ra'anan]

i would never use a pc power supply for a hps light

no a pc power supply wont fire a hps light as there is no capacitor/igniter to fire the bulb so it will not work

yeah, also the transformer board in the PSU makes rewiring just a little more complex than the components themselves, I suppose its theoretically possible to rewire the white/black lines into a ballast/ignitor, but you'd be left with a whole bunch of live orange wires making it a little hairy...

 

[WattSaver]

just spend $26 and get the right components. http://www.ballastkit.com/highpressuresodiumhpshidballastkit-p-333.html

 

[zvuv]

What WattSaver said.

The ballast for an HID light is both a transformer and inductor. As a transformer it ramps up the house voltage to about 400V depending on the bulb. A PC power supply produces 12v & 5v. Most likely it's a switching unit which means the transformer is an itty bitty thing designed to run at 40khz instead of 60 cycles. Even if you found a transformer that gave you the voltages, you still have to match it's impedance to the lamp to get the ballast part of its function. The ballast for an HPS also includes a special coil to work with the ignitor and generate the high voltage starting pulse.

I am all for DIY but this is not a system you can mess about with unless you have deep knowledge of these circuits. Wiring them up is simple but selecting components is not. I say buy the ballast kit wire it up and congratulate yourself that you have been more resourceful and bolder than 90% of the growers here.