120-277 volt Ballast wiring

[mbrooke]

Is it a code violation to have an intellivolt ballast rated 120-277 be used on 208 or 240volts, ie to be connected across both hots?

 

[SparkyHC]

The answer is 110.3(B) Listing and labeling....
From the pictures I can see on the web show ballasts labeled for 120 - 277 volts, my understanding is that means
any voltage can be applied between 120 and 277... If they are labeled 120/277 volts the applied voltage is either 120 or 277...
So IMO my vote is, Yes.
(does the ballast label show a connection to a "neutral"?)

 

[mbrooke]

The answer is 110.3(B) Listing and labeling....
From the pictures I can see on the web show ballasts labeled for 120 - 277 volts, my understanding is that means
any voltage can be applied between 120 and 277... If they are labeled 120/277 volts the applied voltage is either 120 or 277...
So IMO my vote is, Yes.
(does the ballast label show a connection to a "neutral"?)

The ballast can operate anywhere between 120 all the way through to 277. The only issue is I cant find anywhere a specific function of the white lead.

 

[junkhound]

Code violation yes due to labeling.

Intellivolt is a phillips brand, I have not taken one of those specific ballasts apart to draw out the internal circuitry, may be different than described below;

however,
I have taken Motorola M4 type electronic ballasts apart and drawn out the circuit.
Both the white and black wires go to a full wave rectifier bridge, then to a PFC boost circuit.
No connection to the case anywhere, not even a 0.02 uF cap <G>.
So, no problem using that type ballast on 240 V split 120/120 line. Internally, there is a 3A fuse on the black wire, so to be 100% safe, if you put a 3A fuse on the white wire and paint it black, it is a 100% symetrical circuit.
Doubt an inspector would know the internal circuit of all electronic ballasts so likely would not OK that approach either.
I do use some plug-in 277V ballasts in outbuildings across 240 120/120 circuit, no problems.

 

[mbrooke]

Code violation yes due to labeling.

Intellivolt is a phillips brand, I have not taken one of those specific ballasts apart to draw out the internal circuitry, may be different than described below;

however,
I have taken Motorola M4 type electronic ballasts apart and drawn out the circuit.
Both the white and black wires go to a full wave rectifier bridge, then to a PFC boost circuit.
No connection to the case anywhere, not even a 0.02 uF cap <G>.
So, no problem using that type ballast on 240 V split 120/120 line. Internally, there is a 3A fuse on the black wire, so to be 100% safe, if you put a 3A fuse on the white wire and paint it black, it is a 100% symetrical circuit.
Doubt an inspector would know the internal circuit of all electronic ballasts so likely would not OK that approach either.
I do use some plug-in 277V ballasts in outbuildings across 240 120/120 circuit, no problems.

Ive been looking at the Phillips catalog and even the labeling part shows nothing for or against it. Black and white just labeled "LINE".:happyno:

I remember those Motorola ballasts! Non encapsulated; those were fun, every time I found one dead I would pop the cover off just to see what failed. I think the actual lack of encapsulation killed them off faster, often the areas around the main power transistors/inductors was dark brown compared to the rest of the board. The ones I remember were 277volt and had a vari resistor on both hot and neutral connected to the case, but other than the fuse it was 100% symmetrical all the way.


The ones in question have been operating some time now, but more need to be added on, along with about 5 that need replacing but that is small compared to ones in service, all operating fine .

 

[jumper]

Is it a code violation to have an intellivolt ballast rated 120-277 be used on 208 or 240volts, ie to be connected across both hots?

Nope.

Even legal and works on 208V-G 1 phase.:happyyes: