1000 Watt Metal Halide Amp Draw

Caudill Mades1953 · Sunday, November 21, 2021

Strange problem with 1000 watt metal halide bulb.

Hi everybody, I was wondering if any of you had any ideas on whats going on with my setup.

For a uni project I needed to have a really bright light source, so did a little research, decided to get a metal halide bulb. bought all the parts (ballast, capacitor, mogul base, 1000w bulb, correct wires)

wired it all up, plugged it into an extension cable, and took it into the middle of the garden (in case something happened) turned it on, and voila it worked fine. So over the next few days I did some experimenting with the light (long exposures in dark areas, shadow stuff, projection. etc)

BUT i always used the same extension cable when i was doing this (extension cable is 50m long, rated at 13amps, over 3000 watts when fully unwound)

Today I tried plugging it into the mains w/o the extension cable, it lit up, then died all within the space of 5 seconds - i checked and sure enough the fuse had blown. (it was a 13 amp fuse, and the ballast is only supposed to draw 8.5)

anyway, after much experimenting and many blown fuses later, ive found out the only way to get the light to work is to first plug it into the extension cable?! any other combination and the fuses blows.

So, im stuck tbh. the only thing i can think of is that the extension cable is acting as some sort of current time delay? and perhaps the ballast is drawing more than 13 amps on initial startup of the bulb.

here is a pic of the setup i have cobbled together.

Circuit diagram:

(I have it wired up for 240v, not 230v)
also im not sure if capacitors have negative and positive or not, it wasn't marked on the one i got.

Ballast info: (rest on the circuit diagram)

Capacitor Uf. 100
Height 98 mm
Ignitor SI52
Lamp 1000w
Length 220 mm
Width 116 mm

capacitor Info:
1000 Watt Metal Halide Capactior
24 uF (Microfarads)
480 VACr (Volt Rating)
Case Depth: 1.75" Oval
For Use with Ballast Voltage: 120/208/240/277/480
Qty: 1

Lamp info:
MVR1000/U/BT37 1000W METAL HALIDE LIGHT BULB

Base info:
New Leviton 8746 HID Mogul Lamp Base 1500W, 600V

Extension cable is 50m long, and (fully unwound) is rated at 13amps and 3000 watts

I think thats all the info i can give.

any help would be very much appreciated.