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Joined: Oct 2000
Posts: 2,722
Scott35 Offline OP
Broom Pusher and
Feel free to comment, suggest, question, or discuss the schematic[s] for HID Reactor type Ballasts, located in the Technical References Section under the subject heading of:
HID Ballast Schematics - Reactor type

Any and all questions on the operations of these devices are welcome! Please don't hold back!
No one has any "Stupid Questions" what so ever! I will try to answer all questions concisely, but you guys know my messages!
Concise means upto 100 words [Linked Image] [joke on myself]

Look for more schematics for HIDs, along with more interesting stuff. I'm drawing, converting and posting them when time permits.
How do some Panel Schedules in Excel 97 format sound? They will be only a downloadable file - not a viewable image in the forum [unless I can figure out how to swing this].
Got suggestions for other stuff??

Scott SET

Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!
Joined: Oct 2000
Posts: 5,392
i guess i'd ask how many styles of ballasts we can expect to see ( the more common ones, i'm sure there are wierd ones), and what the main diff is bettween them.... [Linked Image]

Joined: Oct 2000
Posts: 2,722
Scott35 Offline OP
Broom Pusher and

There's like 5 basic setups of HID Ballasts - each having some sort of tweek for the type of lamp being used.

Also there's a few designs built around controllers, so I'll post a few of these to the group.

These schematics should be very helpful for members that need some tech references for Ballasts, but are unable to find said Data.

Probably the biggest differences in these Ballasts will be how the Reactor is connected to the lamp.
Some will be straight Reactor, some have the P.F. Capacitor in series with the Reactor, others will be Isolation Transformers.
The ones with the Ignitor will be very much the same as the equivalent one without an Ignitor.

I'll add more this weekend!

Scott SET

Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!
Joined: May 2004
Posts: 16
Junior Member
Hi Scott,

Hope your still on after 3 years. i would would like to know if how much wattage does 400W Metal Hallide Ballast(alone) consume.

Like for example if I'm gonna design a 400W MH Lamp how much should i put on "Schedule of Loads".

Hope you got my point.

Joined: Oct 2000
Posts: 2,722
Scott35 Offline OP
Broom Pusher and
Hello Text!

Wow, another "Legacy" Thread brought back to life today! [Linked Image]

For the Volt-Amp Load to enter in a Panel Schedule, find the Apparent Power Requirements of the load(s) served. This would equate to:


"E" = System's Nomimal / Rated Voltage,

"I" = Listed / Nameplate Full-Load (or Running Load) Amperes at a given System Voltage,


"VA" = Rated Load Volt-Amps (or Apparent Power).

The VA Ratings of equipment will be a combination of the True Power (Wattage) "Consumed" by the load, versus the Power Factor (and corresponding Reactive Power, or VARs).

A couple of examples using the 400 Watt Metal Halide Lamp/Ballast Combination are as follows:

System Nominal Voltage: 120 VAC
Lamp: 400 Watt Metal Halide (ANSI M59)


[*] Nominal Power Factor Ballast (0.50 P.F.):
Listed input Amperes at 120 VAC = 6.67 Amps,

[*] Corrected Power Factor Ballast (0.8334 P.F.):
Listed input Amperes at 120 VAC = 4.0 Amps,

[*] High Power Factor Ballast (0.909 P.F.):
Listed input Amperes at 120 VAC = 3.667 Amps.

For example "A", the Load Volt-Amps will be 800 VA. This is the value to enter in the appropriate cell of the Panel Schedule Database (the 800 Volt-Amps).

For example "B", the Load Volt-Amps will be 480 VA, so in this case the value entered into the appropriate cell will be 480 Volt-Amps.

For example "C", the Load Volt-Amps will be 440 VA, thus in this case, the value of 440 Volt-Amps would be entered into the Schedule's appropriate cell.

(BTW, these examples reflect only one Fixture, or Lamp/Ballast combination. Add VA ratings per number of Fixtures on a given Circuit, then enter that data to the Schedule's cell or cells).

Here are the complete figures for "A" through "C" above:


[*] True Power (Wattage) = 400 W,
Apparent Power (Volt-Amps) = 800 VA,
Reactive Power (Volt-Amps Reactive = 692.82 VARs

[*] True Power (Wattage) = 400 W,
Apparent Power (Volt-Amps) = 480 VA,
Reactive Power (Volt-Amps Reactive = 265.3 VARs

[*] True Power (Wattage) = 400 W,
Apparent Power (Volt-Amps) = 440 VA,
Reactive Power (Volt-Amps Reactive = 183.3 VARs

This should be what you are looking for!


Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!
Joined: May 2004
Posts: 16
Junior Member
Hi again Scott,

I think ur the one who could give more light to these questions:

1. What's the difference between elliptical, tubular and linear bulbs, is there any specific use?

2. Can i switch higher ballast wattage with lower bulb wattage or vice versa? what will be the effect?

4. What if i directly plug the bulb without capacitor or ballast or ignitor, will it blow?
(i dont want to experiment it's quite expensive.)

One more thing, can you explain in "layman's term"? I'm a bit confused.

Thanks again,

Joined: Apr 2002
Posts: 2,527
There is a fair amount of information on HID-lighting electrical characteristics at sites like and

Joined: Feb 2003
Posts: 939
Hi text:

the typical 400 watt metal haldie useally run 430 to 480 watts depending on which ballast it use but most use CWA [ constat wattage autotransformer] for most voltage usage but on 277 or possibly on some 240 volt it can run on reactor ballast to keep the wattage loss at very low level.

but there are some new beast just came out with electronic verison [ one ballast manufacter did make a true dimmable ballast for 400 watt pulse start metal halide verison] i will list that ballast manufacter later once i get their website address

the other issue with metal halide bulbs you have to becarefull with slection and usage because there are few MH bulbs are set to run on certin postion like horzontal burning or base up or base down etc and the other part some area in lower wattage metal halide bulbs requied to be enclosed for safety reason but there are few "open " fixure rated bulbs there too and if you need more info let us know myself and few other can post more details here

merci, marc

Pas de problme,il marche n'est-ce pas?"(No problem, it works doesn't it?)

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