Cellpro Multi4 Announced - Page 4 - RC Groups
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Dec 08, 2008, 07:02 PM
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ptglass's Avatar
I'm going to buy one eventually, but I won't be using my credit card!
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Dec 08, 2008, 07:03 PM
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Sisyphus's Avatar
"Eventually," the product may be available.
Dec 09, 2008, 11:57 AM
Sindland MC SAA
Howard Matos's Avatar


FMA Direct has moved into the final stages of production on the new Cellpro Multi4 charger. We are extremely pleased with the results. This notice is to inform all FMA Direct customers who have placed an order for the Multi4 that delivery on the first production run will begin the week of December 9, 2008. Final assembly and packaging has started here at FMA.

During final development on the Multi4 charger, the design team at FMA Direct made a realization that the discharge feature at 200 mA was inadequate for most applications. Based on feedback from customers and final design meetings, FMA decided to drop the discharge feature from the Multi4 charger. All the other advertised features remain, and make the charger the very best value available for a low to moderately priced charger. If you are not completely satisfied with your pending order because we dropped the discharge feature, please call or e-mail the sales department at FMA Direct and we will cancel your order.

For those of you who would like your order processed, FMA has added an additional measure of security with our ordering process. Accordingly, we are requesting that each customer who receives this notice, call FMA’s sales line to verify credit card information for the backorder. Please call 800-343-2934, ext 3 during normal business hours, M-F, 9:00am to 5:30pm EST. Any sales associate can assist you.

Thank you for your ongoing business. We hope you love your new Cellpro Multi4 charger.
Dec 09, 2008, 12:44 PM
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Sisyphus's Avatar
Quote:
Originally Posted by Howard Matos




During final development on the Multi4 charger, the design team at FMA Direct made a realization that the discharge feature at 200 mA was inadequate for most applications. Based on feedback from customers and final design meetings, FMA decided to drop the discharge feature from the Multi4 charger.
For those of you who would like your order processed, FMA has added an additional measure of security with our ordering process.


But wait, there's more....
Dec 09, 2008, 02:39 PM
Questionable judgement
bracky72's Avatar
I'm glad I went ahead and ordered a 4s using my $10 off instead of waiting. Being able to discharge a charged lipo to storage voltage was one of the features that I was on the fence about.
Dec 09, 2008, 03:46 PM
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SteveM732's Avatar
Quote:
Originally Posted by bracky72
I'm glad I went ahead and ordered a 4s using my $10 off instead of waiting. Being able to discharge a charged lipo to storage voltage was one of the features that I was on the fence about.
Yah, I got to say that even 200 mA beats 0 mA. Some people do need large discharges and are in a hurry, but I would rather have a nice, slow, controlled discharge than use a watt meter and 40 watt fog lamp like I use now. It is good they are listening to customer feedback, but I'm not sure I agree with that decision.
Dec 09, 2008, 03:51 PM
Registered User
I'd have to second that. I was ready to order until I saw they pulled the discharge feature.
Dec 09, 2008, 05:35 PM
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DarkStarPDX's Avatar
Quote:
Originally Posted by Howard Matos
During final development on the Multi4 charger, the design team at FMA Direct made a realization that the discharge feature at 200 mA was inadequate for most applications. Based on feedback from customers and final design meetings, FMA decided to drop the discharge feature from the Multi4 charger. All the other advertised features remain, and make the charger the very best value available for a low to moderately priced charger. If you are not completely satisfied with your pending order because we dropped the discharge feature, please call or e-mail the sales department at FMA Direct and we will cancel your order.
Hey Howard,

I am, like others, disappointed that FMA decided to remove this feature. I'm curious if this was something removed in the hardware or if it was a software change that could be added back in by the user? (voiding the warranty, etc or maybe in the Charge Control Software)

I was looking forward to be able to do cycling on some of my various packs and really liked the idea of having a system I could interface with my computer...
Dec 09, 2008, 06:46 PM
Registered User
Only guessing here but it seems to me that the original concept was to offer a limited discharge feature by using the balance circuitry which explains why it was such a low rate.

Discharging at 200mA is possibly useful for cycling NiXx Rx/Tx packs but is painfully slow for most LiXx packs. The main use of discharge for LiXx is to return a fully charged pack down to storage level. For many users, having to wait 5 to 10 hours to achieve that goal is not going to be acceptable.

If the feature was removed due to reliability/longevity problems with running the balance hardware full bore for anything up to 20 hours at a time then it makes sense. Otherwise as recent experience with another popular charger has shown, the majority of users would rather have even the slow discharge feature than none at all.

My guess is that they have simply removed the feature from the software, no changes to the hardware, so with enough pressure from customers they would have the option to add it back in a future firmware upgrade.
Dec 09, 2008, 06:54 PM
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Operators are standing by....
Dec 09, 2008, 08:26 PM
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Hi Ken, Discharge function requires a MOSFET, much beyond the capability of a balancer to bleed off the high cells. The chipset was probably pulled from the design due to either cost or heat. Some people feel the feature is not necessary, but I use the Storage function (discharge) all the time. Hence the change in the Hyperion DUO-II. In a multi-chemisty charger with ni-xx support, this feature would be used quite often.
Dec 09, 2008, 09:30 PM
Registered User
G'Day Evan,

The balance bleed circuit typically uses a FET per channel and 200mA is a typical balance current so I believe that the hardware would already be in place to handle the load/heat. This is the same strategy used recently to add 300mA discharge capability via a firmware upgrade to another very popular charger in response to persistant user demand. Subsequently that Mfr released a new version of the charger with dedicated discharge hardware (new FET and fan) to give it 50W discharge capability. The price went up $30 to cover it.
Dec 10, 2008, 08:44 AM
Sindland MC SAA
Howard Matos's Avatar
Hi,

Originally, we thought utilizing the balancers to facilitate 200 mA discharge feature would be a no-brainer. This is of course why we published the spec before we completed the R&D, and our preliminary testing supported the original assumption. But once we got deeper into it, we realized that it would take additional hardware to make it feasible and reliable. At this point, the decision was to re-design the PCB to meet our previous published spec, or to remove the feature altogether. Had we elected to re-design, it would have meant discarding the first batch of production, plus another 1000 bare PCB's. There would have had to be changes in the charger enclosure to accomodate additional heat sinking, additional components, a price increase, and of course dreaded delays that customers do not tolerate well. When we started to look into it further, we realized that doing all this to give customers a feature which was already sub-optimal (only 200 mA) did not make sense. We realize that some will be disappointed by this change. This is why we broadly publicized it. This is not simply a software issue that can be turned on later. It would require a new design and ultimately a new product. Whether or not we elect to pursue that option remains to be seen. But we are confident that for the money, the new Multi4 will prove to be an exceptional value to meet the needs of the market as a substantial improvement to the original Cellpro 4s charger. After all, this was originally intended to be a charger and a great charger it is. We can't wait to get them out in the field and see the reaction.
Dec 10, 2008, 09:12 AM
I will be an angry old man!
marc1's Avatar
... time to start looking for another charger then.
Dec 10, 2008, 09:16 AM
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But wait, there is more....