Multi Tap Ballast Lighting Fixture

[Essel30]

I bought a Light fixture that has a Multi Tap Ballast, originally wired for 277v

imgur.com/gallery/nPxl4sf

My source is the standard 120V so as per instructions, I changed the wiring from the 277v line to 120v.

What's strange is, when the wiring is set up for 120v, the voltage to the lamp boosts up to 190v.But when the wiring is set up for the 277v originally as per stock, the voltage to the lamp drops to ~120v.

When I check the voltages coming out of the ballast, the readings properly reflect how the wiring is (120v or 277v)

What's going on?

Is my ballast/transformer faulty?

FWIW this was from a "NEW" condition off of an ebay seller.After speaking with a technician from the manufacturer, I was told it's inadvisable to purchase lights from ebay and he thinks its a faulty transformer.

Thanks for your help!

 

[cybrdyke]

That's a terrible picture. Can you tell us the model number of the ballast? It's probably on a sticker on the side of it. Or at least the exact lamp that it's supposed to be firing?
There is both an ignitor and a capacitor on the circuit. If you are measuring voltage at the socket these two components can screw up your measurements. In fact, if the ignitor is working, it can put out quite a lot of voltage and it's kinda dangerous to measure it.
Good luck,
CD

 

[alfredeneuman]

Be careful! The HPS lamp's ignitor output voltage is 2.5kV or more

 

[Bert_]

Be careful! The HPS lamp's ignitor output voltage is 2.5kV or more

^This if the ignitor is working it will probably smoke your meter. Disconnect the ignitor if you want to measure voltage.

It's not very clear but it sounds like this is a 250W HPS wallpack?

190V is about right, my HID pocket guide claims between 175-225 at the lamp socket. This is for an S50 (250W HPS)

The real question is have you tried a lamp in it?