Electrical problem strange voltage

IrisKitty

New Member
So I'm setting up my rooms, turns out I had a free double pole 240v 20amp breaker free on my main panel. It's 10/3 wire, and I checked it before I wired everything up to make sure it was in order.

Off the line coming from breaker I installed a junction box and split the line in two also using 10/3 wire. Those lines each run into their own Tork 1104 240v mech timer. One timer splits into two 240v 20amp outlets, the other feeds just one 240v 20amp outlet.

Off the timer with two outlets I am running a digital 1000w dimmable ballast with a 1000w HPS. There is nothing yet hooked up to the other timer or other outlets. In the future I will be running 3 1000w digital ballasts total, but for now only one is hooked up.

So here is my problem, when my ballast turns on and my bulb fires up, the voltage on the other 2 outlets reads 1,500v - infinity. On each hot leg to ground, both legs together, just the ground alone with the common probe touching nothing. Also every bare metal spot on my timers reads the same. But when I check the power at the main panel it's normal. Before the bulb fires up and just the ballast is on its normal. Everything runs cool to the touch, I've touched the bare metal parts on the timer, such as the on off switch and I didn't die, that was before I took my readings btw. The ballast and bulb run fine. To try to trace back the problem I checked all my connections, and did a continuity/ohm test all the way back to the main panel on all 3 wires (both hots & ground). And I did this at each outlet, at each junction box, everywhere I could everything checks out, little to no resistance. To check continuity I switched the main off disconected the wires from the 20amp breaker and used a jumper wire to make a circuit with each line. My meter is digital and was set to the 200 ohm setting the smallest on my unit, the largest amount to f resistance I encountered was 00.9 the others were 00.6 and when I touch the leads of my meter together I get 00.6.

I have a diagram to show my wiring, I don't know how to make a wiring diagram so bare with me.
wirediagram.jpg
 
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IrisKitty

New Member
How do I remedy this, would this mean that the bulb socket is not grounded properly?
ok so I tried 4 different electronic ballasts, all give me around 1,500v of stray power. Then I dug out one of my old magnetic ballasts, hooked it up with the same two cords as the others and poof, no voltage leak?!? Wtf??? So my question is this, could I be using an incompatible power cord for the digital ballasts? They are 120/240v and you just switch the cord to change voltages through the same plug. So could it be that if the cord is wrong it's treating my 240 power like 120? I would imagine the stray voltage would have to be coming from the bulb side since the voltage is stepped up. I'm even more confused now that using a magnetic ballast fixed the situation...
 
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Eternal

Well-Known Member
So the lamp operates normally? The only way i can see this happening is somewhere on the ground on the lamp side of the ballast, but if you were getting 1500 volts to ground, that should be creating one massive amount of short circuit current and it would be popping the breaker instantly. You would be getting electrocuted if there were 1500 volts on your ground and therefore on the box that your able to touch.

You said you are getting 1500v with one lead on ground and the other free air? Sounds like false readings perhaps those ballasts are having an rf interference with the internal circuitry of the meter.
 

IrisKitty

New Member
So the lamp operates normally? The only way i can see this happening is somewhere on the ground on the lamp side of the ballast, but if you were getting 1500 volts to ground, that should be creating one massive amount of short circuit current and it would be popping the breaker instantly. You would be getting electrocuted if there were 1500 volts on your ground and therefore on the box that your able to touch.

You said you are getting 1500v with one lead on ground and the other free air? Sounds like false readings perhaps those ballasts are having an rf interference with the internal circuitry of the meter.
RF interference is the only thing that makes sense to me too. Ty for your input!
 

SPLFreak808

Well-Known Member
So you probe your 240 line and get 1500 ac? Probing hot to hot should read 240VAC +/- , hot to gnd/N should read 120VAC +/- if you have an open/loose circuit then that could cause the infinite reading. I dont see it possible, a running ballast, reading 1500 vac at the input. Bad probe connetion or failing leads. If you do probe the circuit with one end and have the other probe open then yes, you will get strange readings.
 

IrisKitty

New Member
So you probe your 240 line and get 1500 ac? Probing hot to hot should read 240VAC +/- , hot to gnd/N should read 120VAC +/- if you have an open/loose circuit then that could cause the infinite reading. I dont see it possible, a running ballast, reading 1500 vac at the input. Bad probe connetion or failing leads. If you do probe the circuit with one end and have the other probe open then yes, you will get strange readings.
If you read through my post, I've done a continuity test on every thing and it all checks out, and running a magnetic ballast everything checks out. It's only when running my digital ballasts that the strange readings show up. I didn't intend to take a reading using only the common probe, I was simply mentioning that the same readings show up with just the common probe connected before I touch another hot leg.
 

SPLFreak808

Well-Known Member
If you read through my post, I've done a continuity test on every thing and it all checks out, and running a magnetic ballast everything checks out. It's only when running my digital ballasts that the strange readings show up. I didn't intend to take a reading using only the common probe, I was simply mentioning that the same readings show up with just the common probe connected before I touch another hot leg.
ok i see. backfeed from the bulb to the input side is extremely uncommon unless you have a bad ballast. it sounds like you might have some kind of induced voltage from the ballast output cable to the input cable, this does not carry enough current, but it has enough voltage to give you an abnormally high reading. if you have any output lines running next to your input lines, then seperate them, a broken or kinked output cable could easily give off induced voltage and shock your ass if you grab it while its running.
 

IrisKitty

New Member
I have the cord to the motorized track the lights on tied to the lamp cord, so they can move together and not lay on the hood. But I used the same cords for the digital ballast as I do for the magnetic ballast. I've also switched cords, switched bulb sockets, run it without the cords tied together. Still the problem is there with the digital and absent with the magnetic ballasts. If it were induced voltage, wouldn't it be too high? I guess if my bulb was at end of life the magnetic ballast would compensate by giving the bulb more juice, but I didn't think digital did this? Also I've tried 4 different bulbs, and get the same voltage readings. As soon as I can I'm getting an analog multimeter and test with that, maybe it won't be as, or at all sensitive to RF.
 

Eternal

Well-Known Member
The fact that the meter read 1500v with one lead on ground and one in the air tells me it's rf interference.
Only happens with digital ballast - rf interference.
If there truly were 1500v anywhere but the output side of the ballast, your ballast and bulb would be fried, and I am not aware of any circumstance including equipment failure where this would possibly occur without creating a short circuit. The way transformers work, I simply cannot see how the voltage could come back to the inputs without being stepped back down by the transformer. on the ground, I could see, but that would be popping the breaker instantly due to the massive amount of short circuit current that would be created.

Good call on trying a different meter, let us know how it goes.
 
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