Fixing a Novatron

**Cletus** · 11-Oct-2012, 10:23

I don't think anyone should be arguing or putting anyone else down over this. I'm pretty sure the OP got the point and either chose to take the advice here, or not.

Either way - and I'm afraid I contributed to this too - there's no reason to continue this pissing contest over who knows (or thinks they know) more about capacitors and the hazards of working with them, then the other. There are many ways to skin a cat and everyone's experience is different. I don't think anyone's advice to the OP was intended to do anything other than dissuade someone from getting into something that could seriously injure, or kill and it seems that was accomplished.

Personally, I've never even seen the inside of a Novatron pack, so I should have probably cooled it on all my righteous "advice" a while ago. I just know that capacitors can be dangerous to work around, even when you do know what you're doing, and leave it at that.

(listen to be being all diplomatic...I'm sure I'll catch hell for that now!)

**BetterSense** · 11-Oct-2012, 10:36

Did anyone read my original post? I'm not messing with the pack. I'm only working on the head, which has one measly 100uF capacitor in it.

**Leszek Vogt** · 11-Oct-2012, 10:44

Although I've heard about the dangers of messing with flash units, at least in anecdotal sense, it's helpful to have this discussion. Perhaps I should add:minus the chest thumping. Appreciate the info.

Les

**Steve Smith** · 11-Oct-2012, 11:07

Originally Posted by BetterSense

I'm only working on the head, which has one measly 100uF capacitor in it.

Do you mean 100nF rather than uF?

Steve.

**Cletus** · 11-Oct-2012, 11:33

BetterSense -

Against my better judgement, I'll chime in one more time. I think everyone understands you're just working on the head and not the pack. This discussion spun out of control awhile ago, including me and with varying degrees of knowledge and experience, chiming in their two bits about how risky it is to work on studio strobe gear in general and the inherent dangers of capacitors.

In my opinion, which really is NOT an expert one, despite my earlier remarks, the danger lies when you start plugging in the head and testing it after your repairs. Or also, as Rick Denney mentioned, the chance that there is another capacitor in the head that you may have overlooked that could store up quite a wallop. You said there is a 100uF cap in the head, which is more than enough, depending on the voltage (the rating printed on cover notwithstanding) to deliver a pretty serious electric shock.

Also, if something doesn't work as expected, or even if not, there's still a considerable risk of shock when charging the pack, plugging and unplugging the head to take it apart again, etc. On top of that, the fact that Novatrons are (from what I've read and heard) notorious for discharging unexpectedly - especially if it decides to discharge, at any time, to the case or the metal head plug with you electrically connected to it!

Just be careful and good luck getting your head working...

**Steve Smith** · 11-Oct-2012, 12:03

Originally Posted by Cletus

You said there is a 100uF cap in the head, which is more than enough, depending on the voltage (the rating printed on cover notwithstanding) to deliver a pretty serious electric shock.

If it's that dark red component in the pictures, it's either 100nF rather than 100uF or it's of a fairly low voltage.

Steve.

**Steve Smith** · 11-Oct-2012, 12:04

I suspect that as the trigger capacitor is in the head, then the capacitor which is discharged into it to create the triggering pulse is also in the head and this is it. If so, it will be in the 10nF to 220nF range.

Whilst this capacitor can also charge up to a couple of hundred volts, the energy stored is small. It does no harm to the contacts in a shutter.

Steve.

**E. von Hoegh** · 11-Oct-2012, 12:09

Originally Posted by Leszek Vogt

Although I've heard about the dangers of messing with flash units, at least in anecdotal sense, it's helpful to have this discussion. Perhaps I should add:minus the chest thumping. Appreciate the info.

Les

Too bad they don't get so upset about driver safety, or the importance of being an informed voter.

**jnantz** · 11-Oct-2012, 13:28

hi bettersense

you might consider just sending the light to novatron ( they are in TX )
getting it repaired by them, or getting a refurbished one
directly from them, they are pretty inexpensive and will have a warrantee .
the batter pack novatrons don't really put off very much light from what i remember,
at least the old ones that were like 200WS split between 4 heads ...

good luck!
john