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Colin D
27-Apr-2014, 19:32
I've hit a technical problem with my Multiblitz Profilite 200 flash unit.

One of the flash units started leaking, just a drop although more inside, what appears to be a clear light oil substance and is no longer working. I had it pointed upwards at the time and it was not turned on but plugged into a power board. After plugging a LED light power pack for a recharge into the same power board a terrible pungent smell filled the room, after searching for an hour I found the oily stuff coming out of the rear air vent of one unit. Taking off the front cover the substance appears to be coming from around the globe housing. The flash globe and the modelling globe look to be still ok.

Plugging the LED battery pack into the power board is the only thing I can think of that I have done differently, but what has happened. Any ideas?

BTW, the smell is nothing like a electrical burn smell, it is pungent and rotten like. I have no idea what would have this substance it it.

Any assistance appreciated.

Amedeus
27-Apr-2014, 19:51
Most likely you have an exploded/leaking electrolytic capacitor. These can be replaced but it might not be worth it from a repair cost perspective unless you know someone who's good at fixing random electronic (high voltage) stuff ...

Colin D
27-Apr-2014, 20:22
Ah $#!t, not what I wanted to hear but probably along the lines of what I expected.

Cheers Rudi, that will give me something to start with at least.

Leigh
27-Apr-2014, 20:47
When units develop physical leakage as you describe, they're dead and cannot be resurrected.
A shop may or may not be able to repair it, depending on the exact internal damage.

The following information applies to units that appear to be in good condition.

Electrolytic capacitors typically have a rather short shelf life, particularly those used in consumer gear.
Manufacturers' datasheets recommend that these be re-formed if they sit unused more than 6 months.

If you're trying to use a unit that's sat unused on the shelf for more than six months, start by powering it up in stages over a period of several days. This won't guarantee proper operation, but it may restore operation if such is possible.

If any abnormality is noticed, immediately turn the unit off, discontinue this process and discard the unit.
Note that defective electrolytics have been known to explode, although this is a rare occurrence.

On the first day, power it up for no more than ONE minute, then turn it off and leave it alone.
On the 2nd day, on for two minutes, then off. Then 4, 8, 16, and 32 minutes on days 3 to 6.

On the seventh day it will be healed if it can be.

- Leigh

Colin D
27-Apr-2014, 21:00
Thanks Leigh, I had used it the day before and over a number of weeks before that. Come to think of it it didn't fire the last time I took a test reading with the light meter, that might be when it happened, it was late so I didn't bother looking into it. Strange thing is the smell didn't arrive until the next morning, mmm, a mystery indeed.

What else causes these things to give up so I don't kill the other one.

Looks like I need to find a friendly electro tech then, or discard it which would be a kick in the guts and wallet.

Leigh
27-Apr-2014, 21:14
Thanks Leigh, I had used it the day before and over a number of weeks before that. Come to think of it it didn't fire the last time I took a test reading with the light meter, that might be when it happened, it was late so I didn't bother looking into it. Strange thing is the smell didn't arrive until the next morning, mmm, a mystery indeed.
An electrolytic has a pressure relief valve, which is a small rubber diaphragm covering a hole in the housing.
The electrolyte inside has significant moisture content, so it releases steam if it gets too hot.

If the steam pressure rises significantly, the valve breaks to release the pressure. Should that occur, the moist contents will leak out over a period of time, if the breached valve is toward the bottom.


What else causes these things to give up so I don't kill the other one.
The electrolytic capacitors are the only component with a known reliability issue.
Other components may fail, as with any electrical product, but those don't have known short lifespans.

If you read the datasheet for any regular consumer-grade electrolytic, it's only rated for 2000 hours of operation.
That's ONE year of normal 9 to 5 office work.

The trick to keeping these in good condition is to use them for 10 to 15 minutes at least once a month.

- Leigh