Lambuster

Seriously pissed off at the moment.



Got a couple of hps 400's second hand last week, knowing that only one bulb was coming with them. When I plugged the bulb in, all I was getting was a blueish discharge at the bottom of the tube, so I plugged it into the other set to test it. It did the same thing in the second unit so I thought "oh well, it's just the bulb - it IS second hand..."

Went out today to buy a new hps bulb, got it home, plugged in, and..... nothing. At all. Not even the blue glow.

"****!" thinks I. Took it round to a mates, along with the old "dead" bulb to try in his hps lamp and not only did the new one work, but so did the old one.

Ignitor???

Is this the most likely culprit?

I just get a slight hum from both my units and none of the 'start-up' sound. I took the ballast case apart and can find no obvious damage - wires loose, burnt components etc.

Is there any way to test the ignitor, barring replacing with a working unit? And the next question... are they expensive to replace and where might I find one of these little critters in the UK??? FYI it's a Sunlight Systems hps 400 ....

Appreciate any advice (as always!!!)

harrad

Lambuster,
Did you make sure that the ballasts were wired for the right mains voltage? Was the lamp fully seated in the socket? One would think that a new lamp would have displayed at least the same symtoms as the old one.

Ignitors do fail. In the U$ replacements are about $30. In this instance it sounds like a wiring problem. Failed capacitors can also wreak havoc. Start with the simplest solutions and work your way up.

Check the wiring and voltage specs against any info printed on the ballast. A blue glow from only one end sounds like a Metal halide lamp, not a HPS. Check for the existance of the ignitor (Small can with 3 wires) a MH setup usually won't have one. If you decide what you have is a MH setup after all, the problem is most likely the capacitor. Also about $30 U$.

Always take the bad part with you when seeking a replacement. Some shops might test the whole fixture for you if you take it with you. It's for the car park right?

Hope this helps! Harrad.

Sanclem

Note the spring in the center of the socket. Hid bulbs get real hot and weaken the spring. Most Hid /mn/hps sockets die way before the ballast or starter crap out. Look at the bulb and the bottom will be eaten up by the bad contact. I'm just guessing but changed out many, on the lighting crews.

Lambuster

I've checked everything I can possibly think of... the sockets seem to be fine, the wiring is all secure and configured for the correct mains supply and the transformer is humming gently with the power on, so I know that, at least, seems to be ok. There's just no start-up from the bulb...

When I tried the same bulbs on my friends setup there was a distinct noise (from the ignitor?)as the bulb fired up. Is this fairly standard for all hps fittings? It was very much the same as the sound you get from a fluoro when it starts up (probably because it's the same principle in action?), but there is no noise at all from my ballast, which suggests to me that the ignitor is fubar.

Incidentally, the old bulb is a Planta which has an extra element or something, does it not? That may well suggest the presence of the blueish tinge, as it is most definitely a hps..

Thanks for the replies, I'm gonna pull one of the ignitors and take it round some of the lighting places tomorrow to see if they have any replacements, cos the only other places I've seen that have them are mail-order, and the few hydro shops that do exist round here only keep the whole ballasts in stock - not the parts.

Lambuster

Ok here's the latest....

got a new ignitor today, put it in, flipped the switch and.... still nothing.

still getting a hum from the transformer, so i'm kinda assuming that's still working

it's gotta be the capacitor.

please don't let it be the transformer.

oh, please don't let it be the transformer.

i'm trying to think positive, especially as i got a good deal on a pair of twin tube 2' fluoro's for the seedlings today, and that HAS cheered me up some. £11 a piece including the tubes should keep me going for a little while till i can get the hps 400's going.

weedchiller

Thats a good point about the bulb holder. They cause enough problems in domestic lighting for it to be obvious, but I'd overlooked it in HID.
Check out www.21stcenturygardens.co.uk
Under lighting accesories you'' find this;

250W Transformer 1242 £19.00 (£22.32)
400W Transformer 1243 £20.50 (£24.09)
600W Transformer 1244 £28.00 (£32.90)
1000W Transformer 1245 £52.00 (£61.10)
250/400W Ignitor 1246 £7.80 (£9.16)
600W Ignitor 1247 £10.45 (£12.28)
1000W Ignitor 1248 £12.30 (£14.45)
45uf Capacitor 1249 £4.85 (£5.70)
50uf Capacitor 1250 £4.95 (£5.82)
65uf Capacitor 1251 £5.30 (£6.23)
GES Ceramic lamp holder 1253 £7.80 (£9.17)

Hope it helps