Metz NiCD cluster for 45 CT/CL series flashes

Does anyone have any idea of how to disassemble one of these to replace the cells, short of breaking it? I have 3 packs for my 45 CT-1 whose cells are on their last legs, and the thought of replacing the 500 mAh cells with 1100 mAh is gnawing pretty hard!

Before anyone suggests using NiMH cells in the Metz NiCD pack, it's important to consider that the charger for the pack is just a transformer with a 7V AC 600mA outlet and that the rectification and current limiting circuitry is in the pack itself. The same charger is used for the Dry-Fit pack with the 60 CT series flashes. Metz also warns that you shouldn't use NiCD or NiMH cells in the "standard" AA holder as the contacts aren't designed for and can't properly handle the extra current these cells can deliver.

Any clues/insight would be greatly appreciated...

There is a website that covers replacing the batteries. Everything from cracking it open to replacing the batteries. It also covers the issues with switching to Nihm.

Of course I can't find the #$C#$!@!#@ thing right now.

http://www.pbase.com/dvas/metz_45cl4_battery_pack_conversion

That's a different one.

http://www.xs4all.nl/~wiskerke/artikelen/metzengl.html

Different again.

Found it.

http://www.uglx.org/metznicd

Never claimed to be fast did I?

That's a complete BS unless you're making three flashes per second - really, the plastic lamp housing would melt down sooner than the contacts in battery pack, in normal shooting mode. Their whine about too high a current through circuits is not relevant, too - in a normal mode, again.

bobfowler said:

Metz also warns that you shouldn't use NiCD or NiMH cells in the "standard" AA holder as the contacts aren't designed for and can't properly handle the extra current these cells can deliver.

Any clues/insight would be greatly appreciated...

Click to expand...

Nick Zentena said:

Found it.

http://www.uglx.org/metznicd

Never claimed to be fast did I?

Click to expand...

Nick, I owe you a beer! (or many beers!)

This is just another example of why I love APUG!!!

eumenius said:

That's a complete BS unless you're making three flashes per second - really, the plastic lamp housing would melt down sooner than the contacts in battery pack, in normal shooting mode. Their whine about too high a current through circuits is not relevant, too - in a normal mode, again.

Click to expand...

You're probably quite right. I wonder though, why the AA holder and the NiCD clusters use different ground pins INSIDE the flash handle. Perhaps something to prevent turning on the flash while the batteries are charging? I'd love to see a circuit diagram of this thing...

bobfowler said:

You're probably quite right. I wonder though, why the AA holder and the NiCD clusters use different ground pins INSIDE the flash handle. Perhaps something to prevent turning on the flash while the batteries are charging? I'd love to see a circuit diagram of this thing...

Click to expand...

NiCd's put out a lower voltage than alkalines, and provide less current (greater internal resistance), so I assume the flash circuit is optimised internally to match the different battery types. I wouldn't put NiCD's into the AA's unless I switched the contact over to match. Worst case it could even throw out the metering (though I've no evidence of that).

As for charging - the instructions specifically FORBID charging the pack while it's in the flash.

I've dismantled and repaired a couple of packs - one had a broken connection, and fixed up fine. The other had a damaged charging circuit - it had somehow corroded, but I got it fixed no problem. Trouble is the cells needed replacing too, so while it charged, it still wasn't viable. Maybe one day I'll replace the cells.

Anyway - they're pretty easy to work on even with my clumbsy skill. A bit small and fiddley, but not at all complex.

Ian

The AA holder and NiCd clusters really us different ground pins inside, but the main difference is a small resistor in a NiCd circuit, with quite a negligible ohmic resistance... as I can understand, it's made just for cases when your 45 flash is used with old motorized Nikon F-3, say. Three frames per second, the current going from low inner resistance NiCds HAS to be limited by a resistor. If you shoot normally, there's no way to overheat the lamp and capacitor/inverter circuitry. The flashmeter is of course voltage-independent, if it were depending on cells voltage the normal operation of auto-aperture would have been impossible, as used cells give less voltage etc. - its circuit is more like an integrator of lighting time (close to shutter testers) than a, say, CdS regular resistance-based exposure meter. I use NiCds in my 45CT-1 with AA holders for ages, and the only problem I ever got this way was a bad synchro cord

bobfowler said:

You're probably quite right. I wonder though, why the AA holder and the NiCD clusters use different ground pins INSIDE the flash handle. Perhaps something to prevent turning on the flash while the batteries are charging? I'd love to see a circuit diagram of this thing...

Click to expand...

bobfowler said:

Nick, I owe you a beer! (or many beers!)

This is just another example of why I love APUG!!!

Click to expand...

I'll just send you my pack and you can redo at the same time-))

FWIW, The NiCD Lady Company has Sanyo KR1100AAU AA 1100 mAh Flattops w/tabs for $3.00 each. They also have some good deals on NiMH and SLA as well.

UPDATE

I just recelled my first 45-40 pack... what a pain in the ass! Getting it apart was easy, getting the cells to line up correctly wasn't TOO bad, but getting it back together was a royal pain...

one down, two to go...

Simplest, cheapest "let somebody else do it ofr you solution to redo or replace 45 series battery pack:
three options and I have done the first and third all ready: just take the pack to Batteries+Bulbs and get it rebuilt for about $20. ask them to install the best strongest nicads they have others are even cheaper. they have to figure out how to do it each time because they don't keep records of their work! I know! but moving on, you get a pack that initially recharges from a full flash discharge in 4 seconds and has about 140 full power flashes in reserve, ending with a recycle time of 15 seconds. The first charge will perform a lot less than that, about 50 recycles to full pack depletion. So the reserve on the second recharge improves almost 3-fold and the initial recycle time is shaved by 2 full seconds from 6 to 4. don't put NIMH in it if you don't have the 970 charger because they won't work
#2 buy an off brand (there are Metz ones at B&H)empty AA pack on Ebay for about $8 that you can install store bought AAs in. But then go back to Ebay and buy from China rechargeable lithium AA batteries and charger for about the same price as throw away lithiums in the USA, charge and insert them in the pack, put it in your handle and have fun.
#3 by an NIMH pack from Henry's on Ebay. Henry's is selling them right now for $29 with free shipping. They cost $129 at B&H Photo but you can get a B46 that too with the required Metz charger. You must have t NIMH Metz charger to charge the NIMH packs. One model is the 970 charger and all are expensive. I got one of Henry's and it initially starts with a 6 second recharge time.

So if you don' have the NIMH charger, the most viable and economical and bang for buck options is #s 1 or 2 above.

Just use an external battery like the Quantum Turbo to power the flash and improve the recycle time, compared to what the old NiCads can do for both recycle time and for number of flashes!

wiltw said:

Just use an external battery like the Quantum Turbo to power the flash and improve the recycle time, compared to what the old NiCads can do for both recycle time and for number of flashes!

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yeah I was looking at those, and my reply has always been: then you have a cord running down and a pack like the 60 series. No thanks, i prefer a couple or four battery packs to that. and I have about a 10 foot metz wall power cable for instantaneous recycling that beats all power packs and can recharge the pack while in the unit. if your shooting position is relatively static, with another extention, this is a great power option for the 45s.

I use AA Alkaline in my 45 CT5 in the ordinary battery holders the batteries are cheap enough and I use it rarely in that situation rechargeable cells can be a problem if not used regularly.