Highflight

My Feedback: (4)

The HobbyKing Quattro 4x6s Multi-Charger is relatively new and is getting reasonably good reports in general. Some complain that it "only" charges at 5amps per port (20 amps over 4 ports), but I have no problem with that since my charging is primarily the overnight kind and I come from using a max. 1amp (total over 4 ports) Alpha-4 that has been doing great for quite some time.
But I bought the Quattro thinking it would replace the Alpha-4 because the Litco product is a dead-end since it was never upgraded to handle the newer battery chemistries.
Anyway, I've been wringing out the Quattro, only on Nicads and NinH for now, and I don't like what I'm seeing as described below. What you see below is my own description of what I've found that I posted on another forum, so I've cut and pasted my own post from there to here so that it can get a decent conversation started, and hopefully, yield some answers if other people have found the same that I have and we can try to figure out what's "different" about this new charger.

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OK guys, it's time to take a closer look at the Quattro 4x6s Multi Charger and uncover some things that need to be discussed.

This charger is supposed to handle Nicad and NimH batteries, but I'm getting some not-so-great results and I wanted to post this here and see if anyone else is getting similar results.

Here's the deal: I built three brand new identical Nicad packs from Sanyo batteries. Each of these pacs are 5-cell, 1700mah size packs.
I have a fourth brand new NimH pack which is a 6-cell, 1300mah pack that came in a brand new radio I just bought (Aurora-9).

I did the usual "forming" charges on all four packs, and then ran them all through a series of Disch/Chg cycles on the Quattro to determine how they cycled.

I could list each of the series of cycles to the mah because I kept notes throughout, but I don't think that's necessary unless someone needs to see a cluttered up post, and I can describe the very relevent details of the results very simply.

On each of the four batteries (3-Nicad & 1-NimH), the Quattro would consistently UNDER charge them, and as an obvious result of that, would then report a lower capacity of what the batteries are actually rated at.
Again, I could give the exact numbers, but it's accurate to say that all of the numbers during the cycles routinely gave results that indicated the batteries to have capacities of about 15% to 18% LESS than the packs were actually rated for.
In the past, that's about the point that I would throw a battery away if it could only show a cycle to that percentage of rated capacity. But keep in mind, these are all brand new battery packs.

In order for this to be a controlled experiment, I then ran the exact same cycling of all four of these new batteries on two other chargers that I have; a Litco Alpha-4, and an iCharger 208b.
After performing cycling on each of these four batteries on both of those chargers, in each of these cases, the batteries routinely cycled and reported capacities of around 3% to 8% OVER the rated capacity of these packs.
These "over capacity" readings that I got from both the Alpha-4 and the i208b are very normal for brand new batteries in new condition and are what I would have expected the Quattro to cycle and report as well.

So, for me, the Quattro is clearly not programmed correctly to handle Nicad and NimH batteries.
To answer the questions that I know are coming; yes, I did change the user settings to match the default settings of the other chargers as closely as possible. I even turned off both safety trips (max. time and max. charge) to make sure that the Quattro was stopping the charge using the Delta-V and not timing or *****g out on the charge amount.
I also tried modifying discharge rates and charge rates, but that made little difference.
I haven't modified the Delta-V mv cutoff point on either the NimH or the Nicad settings, but the default settings are fine for any typical NimH or Nicad battery. Besides, in order to put off the Delta-V trip in such a way as to lengthen the charge time, you would have to increase the trip millivoltage, and if you do that, you risk the charger sailing right on past the Delta-V when doing a (safe) C/10 charge because (especially with NimH batteries) the Delta-V slope flattens out at a lower rate of charge. And if the charger misses the Delta-V, you can trash the battery by the time it starts to vent.
That's why I wouldn't recommend that anyone not familiar with battery chemistries mess around with changing the default Delta-V trip points.

I'd like to hear from others who have taken the time to run cycle tests like I have on both the Quattro, and on another charger that they might have, to compare results.
At this point in time, I am uneasy using the Quattro on Nicads or NimH batteries at all, and since the programming is lacking for those chemistries, I have to wonder if the programmer did any better with setting it up to charge Lipos either.

It's also disappointing to think that a firmware upgrade would not be possible at some point, because this is a new charger on the market, and it's not unfair to assume that some tweaking of the product might be desired.
If the results I got are typical, and if this charger can't be upgraded with proper firmware, I think my next step would be to get rid of it and reinvest to get three more 208b chargers which appear to be spot on and very accurate where the Quattro simply isn't.
The Quattro appeared to be quite a "value" for what it claims to do, but if it doesn't do what it claims, then it's no value at all.

Anyone want to offer some more input?

guver

My Feedback: (325)

I guess I have a question then because you said it was "undercharging"

What makes it stop? or to put it another way Does the voltage drop right before it stops?

Highflight

My Feedback: (4)

On any typical smart charger that is also a cycler (including the Quattro), what terminates the discharge stop point is, very simply, the pre-determined voltage that the charger looks for, not any kind of "reverse peak", or any kind of battery "reaction" at all. The bottom is determined by just the simple voltage cut-off setting.
Then what determines the termination of the charge at "full" voltage is when the charger detects that little voltage drop referred to as the "Delta-V".

So a pack's capacity is determined and reported in mah as a function of time based upon the discharge current set, and the total amount of discharge amps (the reported capacity of the pack), typically reported in mah, is what the charger sees between the "brackets" of the specific cut-off voltage at the bottom, and the Delta-V at the top.

In the Alpha-4, both the bottom cut-off voltage and the Delta-V drop voltage (in millivolts) is hard-wired and not user selectable.
In both the iCharger 208b and the Quattro, both of those settings are user-selectable, and both of those chargers have a "Default" Delta-V that can still be changed if desired, while neither of those chargers have a "Default" for the bottom cut-off voltage. The user is on their own to program what they want the bottom voltage to be, while it's recommended that the user not change the Default Delta-V settings (even though they can be changed). Note that both the cut-off voltage and the Delta-V is different for Nicads than they are for NimH, an important distinction when managing packs of those different chemistries.

For my testing as explained in the OP, I use the Alpha-4 results as a "baseline" of proper cycling and charging because it is not only hard-wired for those cycling parameters, but has performed as expected and given results for years and years with two decades of use that have always been dependable as to how the Alpha-4 managed cycling, charging, and reported long-term capacity degradation of old packs. In short, the Alpha-4 has never let me down. Whenever the Alpha-4 has reported a problem with a pack that I didn't think was right, it's always turned out that the Alpha-4 was right and my assumptions as to the condition of the pack were wrong. (I'll add here that while the Alpha-4 is an "obsolete" charger due to it's failure to be updated to handle the newer battery chemistries, it's as good as it ever was for Nicad and NimH management. You'll get my Alpha-4 when you pry it from my cold, dead, fingers ) .

So what's significant in the results I got as noted in the OP is that when I set the 208b to what I felt were proper, safe, and conservative values of the cycling voltage and Delta-V bracket, it set off right away to report very similar results as the Alpha-4, and when I say similar, I mean always on the same side compared to the other (where the one was always a smidgeon higher each time), and well within a very narrow range of expected results for those brand new packs.
But when I then use the exact same parameters for the Quattro that were set in the 208b, the Quattro would consistantly report significantly lower capacities. As I said in the OP, that difference was in the range of 15% to 18% different (lower) than either the Alpha-4 or the 208b. Additionally, I experimented a little further with the Quattro by changing it's relevent cycling settings, but even though it affected the results "a little", it still didn't come anywhere near as close in reported cycling capacities as either of the other two chargers.
In a controlled test, when two disparate items perform similarly accurately, and the other item performs outside of those two, then it only makes sense to believe that the item that performs outside expected parameters is the one that is errant.

guver

My Feedback: (325)

I should re-phrase this. I wasn't very clear.

What makesyourparticular quattro stop the charge cycle? or to put it another way Does the voltage drop right beforeyour particularquattrostops charging?

I'd be interested in seeing the actual numbers from the quattro and the other chargers as well because I have questions about the capacity reported by them. Without seeing the numbers, verifying some numbers on both chargers it seems that on the surface this is merely a case of some inaccurate math, timing, or simply the quattro shutting off sooner than the others (at the same settings) on discharge.

Highflight

My Feedback: (4)

I'm not sure I understand your main question, but I guess you're referring to the voltage drop at the Delta-V trip point.
So yes, the voltage has to drop right before it stops or the charger wouldn't stop charging and would continue on to overcharge (damage) the battery.
The Delta-V point isn't a specific voltage, but rather, it's the drop in voltage at whatever exact voltage the Delta-V occurs.
You ask if the "voltage drops right before it stops" as if I might have been standing there and watching it at that exact moment. However, even if I was watching it, I wouldn't be able to "see" it on the screen because the Delta-V that the Quattro uses for Nicads is 12mv. Since 12mv is 12 thousandths of one volt, we're talking about the same thing as close to 1/100th of one volt. While the display reads out to two decimals, it jumps around a bit while charging because the display lags the real-time voltage as seen by the chip, so it's very unlikely that I could ascertain the moment that Delta-V arrived.

As far as the Quattro shutting off sooner than the other chargers, keep in mind that I set the Quattro at the exact same bottom discharge voltage as I did the iCharger 208b. And since the 208b is in very close agreement with the Alpha-4, then one of the two user-programmable chargers must be wrong, and it's most surely the Quattro that's wrong since it's the exception to the other two.
And if the the Quattro is shutting off too soon, i.e., before it reaches the voltage that I set, then that means that the Quattro is out of spec, and that's the conclusion that I have already reached.

I'm a little aggravated that the charger that is working flawlessly, the 208b, has firmware that is easily upgraded if necessary. So if it was the 208b that was errant, it would have the hope of being reprogrammed to fix any calibration errors. But as far as I know, the Quattro is not upgradeable, so if it's off, it's junk.

guver

My Feedback: (325)

Two other methods might work to verify the charger is stopping at the "full mark". Check the temp rise of the pack or perhaps there's an ending message that communicates "normal delta peak reached"

On the surface it appears that there's nothing wrong with the quattro , it probably is what it is and I would guess that all 4 are the same and all the other quattros are the same too.

If you can somehow verify the "full mark" or simply start with a full pack then we can eliminate undercharging from the equation and look at the bottom point or the middle part.

Highflight

My Feedback: (4)

You're correct about using the temp rise, but that's not a reliably accurate way to tell a full charge. It's more of a safety cutoff than it is an accurate method to stop the charge when talking about Nicad and NimH batteries.
At the charge rates I'm using that are healthy for those kinds of packs, I don't think that using temperature would help that much since I typically don't see ANY temperature rise when charging at C/10 and up to C/8.

As far as the testing I've been doing, I ALWAYS start with a full pack, and typically let each of the chargers go through 5 full charge/discharge cycles. I even started with a full pack as charged on one of the other chargers that do appear to work fine, but the Quattro immediately drops down to it's typical performance level of showing about 82% of the expected capacity of the pack.

I think you're right about all 4 ports operating the same way since they actually do shoe similar results to each other. That would indicate to me that I'm not seeing a "defect" in the charger itself as much as I'm seeing errant programming by the manufacturer. However, I wouldn't be able to verify that unless I bought another Quattro (ain't gonna' do it) or if someone else who has one could run similar test cycles on healthy batteries and let us know here in this thread what their results were.

At this point, it appears that the Quattro is programmed by the manufacturer to be way too conservative in it's operation compared to other chargers. That's good if it means that people unfamiliar with proper charging practices are kept from getting into trouble, but it also means that you'll never get the performance out of your batteries when it comes time to go fly.

Highflight

My Feedback: (4)

I'm a bit surprised that only one person, guver, has shown any interest in the topic, because this particular charger, along with it's other clones, has gotten a LOT of attention since it's been introduced. Plus, it's on backorder more than not, so there has to be a large number of them out there and in use.

I thought that this would prompt more than a few of those owners and users to look more closely at their Quattros. Also, this topic could actually affect many more people because the Quattro appears to be manufactured by the same people as the Imax B6 which looks to be the same charger except for the B6 being a single port charger. Additionally, there are other chargers that are coming out soon that also appear to be made by the same company but under different brand names.

So if the results I'm getting are how the Quattro was designed to work, then there's going to a ton of chargers out there that will be deficient in the same ways as the Quattro.
So, again, I'm surprised that no one else seems to be interested.

redfisher1974

I have been reading with interest, As I am sure others have too.

guver

My Feedback: (325)

It sounds like you have indeed eliminated the full mark as being the trouble by charging on another charger and getting a low reading on the very first discharge cycle with the quattro. There are really only a couple of possibilities that I can come up with since the battery isn't any different and has whatever capacity it has. The trouble that your having seems to be akin to "what to label the pack" and I would guess that you are one of the very few who would see it as a problem. I suppose I am content with labeling the pack with whatever the equipment tells me at the time. When I have two charger that do not agree I just make a note or take that info with a grain of salt when naming my pack.

Anyways back to the possibilities:

The current over time equals the capacity down to a given voltage. If the timer is right on the money and the current is exact then we only have the ending voltage to play with and it can very well be different pack voltages measured by 3 different chargers that are set the exact same way.

The timer should be very easy to check with a stop watch and the current should be easy if you have a way to measure it and it doesn't fluctuate a lot. If so then let's play with the bottom figure. What is the current and the ending volt cut-off of the 5 cell packs that you are using for discharge?

BEAR-AvHistory

Hobby King is comming out with thier own version of this charger built in thier factory. Its on pre-order now. Splits the output to two on each side instead of 4 on one side & should be less cluttered.

A higher output version is a bit down the road.

Flying Geezer

My Feedback: (14)

If you want to look at the peak detection, Radio Shack has a vom that connects to your computer and graphs the voltage of the charge cycle and discharge cycle. It's around $50, software included.

Highflight is right when he says it's hard to watch the readings. The graph will make it easy.

Highflight

My Feedback: (4)

I appreciate the continued suggestions, but I'm not concerned about nailing down what I already know to be the case.

What I'm trying to do is to get OTHER people who have this same charger to also contribute to see what's going on with the design and programming of the charger.

At the moment, I believe that the issue is about design and programming, not a "defect" with my particular charger. But we (all who have this charger) can't know that to be the case or not unless and until someone else can run there own tests and contribute to this thread.

There has to be quite a few out there by now, and I'm sure that many of those owners are members of RCU. I'd sure like to see them be concerned enough to participate and offer some results of their own.

chyorn

I bought one of these about a month or so ago, and just recently aquired enough planes as to have to pull out my nicad batteries again to be able to fly all planes. One battery is a 4.8v jr pro 4n 1100 ma, another one is a jr extra2300 ma 6v pack. Both are about 1.5 -2 years old; still within a useableage. last summer I flew off both of these packs with ledbattery monitors on the sides of the planeswith no problems. The battery monitorssaid the batts were good to fly with even after half a daysflying. A third battery I have is a 5 cell nicad that isa home made job, around 1500 ma. Now, Iran the cycle function for these batteries using the following settings: 5cycles .8 amp charge.8 amp discharge, and the voltage was set at 6 volts for the 5 cell packs, and 4.8 for the 4 cell packs. Now,the charger saidthat all three packs would only hold between 300 to 370 ma on thecharge cycle, and would only put out around 250 to 300 on thedischarge cycle.Now, I find this hard to believe, especially with my home made pack cuz I flew with it 2 months ago for half a dayand not even a full charge and the battery monitor onthe side of the plane said I wasstill good to fly. There is no way that could be true if the pack would only allow me to have 270 ma to work with.

adam

Flying Geezer

My Feedback: (14)

Try cycling the packs several times if they have been sitting for a long time. If that doesn't work, you have a bunch of bad packs, or the charger is false peaking on charge.

mehrshad

I have not this charger but I have a suggestion:
discharge the packs with quatro and charge them with 208 and see the ending mAh.
afterward discharge the packs with 208 and charge them with quatro and see the mAh.
probably it is related to discharging and not charging. so it(quatro) may fully charges the packs.

keredg

Could you not just adjust the delta-V cutoff mv to stop the false peak(if that is what it has) to make it put in the full charge, after all thats what the adjustment is for, no? I ask as i have 2 different makes of battery and i had to adjust one set slightly to get the full charge, the other set works on default, am i doing wrong?

Highflight

My Feedback: (4)

The default Delta peak is 12mv, and it can be adjusted up to (or down to as the case may be) to a max of 20mv.
I tried changing it to 15mv and it did make a little bit of difference, but I still get capacity readings about 200mah short of the 1700mah that the packs actually rate.

Yes, I could try taking it to the max of 20mv, but as you know, any time beyond any drop is technically an "overcharge" and I'm concerned that I could start harming the battery to take it to that point.

The thing is, I am not completely sure yet whether the problem is in the bottom discharge cutoff point or if it's at the DeltaV point. I don't want to extend the wrong end, so I'm trying various things to check that as I get time.
Still, the default 12mv DeltaV should be a perfect setting for charging any Nicad, and even though you can change the setting, I'm a bit uncomfortable doing so when the darn thing should work correctly right out of the box.

Flying Geezer

My Feedback: (14)

When a nickel based battery is started on a charger it increase in voltage rapidly, then in just a few minutes, it takes a big voltage dive. Better chargers have a peak detection holdoff timer that disable the peak detector for a few minutes to get past the voltage dive that will cause a false peak.

Try charging the battery, then as soon as it stops charging, re-start it. If it fully charges you'll know that's the problem.

I don't know if there is an adjustable peak detector holdoff adjustment on that charger. I doubt it.

guver

My Feedback: (325)

I am 99% sure that all the packs and "cycles" have had a full pack and the additional capacity is at the bottom or just a different number between chargers. It is probably just a case of "battery reads xxxx capacity" on this charger kinda like engine dynos. A 500 hp engine may only ever read 450 hp on a certain dyno.

SeaJay

My Feedback: (6)

I am interested in this charger, since I have several High capacity NiMh packs, and this charger seems like it would be the Ticket..

Are there any users of this charger with new insite/info/Opinions on said charger??

Thanks, Craig.

RDaisy

Hi all

TampaRCGuy

My Feedback: (282)

This charger while relatively new, the firmware is based off a 5 year old charger design. The issue that you are having will continue to until the Chinese companies that make these chargers actually do R&D instead of trying to copy other companies products.

RDaisy

I'm not sure big brands have done a lot of R/D about Nimh batteries the 5 past years... And actually i see this charger in Europe with big brand names on it, so who copies who ?

To come back to my problems, i have good news. Last week-end i had very good results with 2 Nimh batteries. The problem was the "not enough" cycling of my packs (Tx pack of my new T8, and a self-made Rx pack that hadn't worked a lot), and a very low charge current which didn't allowed peak detection well (C/10 seems to be very low reading the batteries manufacturer's websites)

Here's what i did :

- Discharge of both batts at C/10, final voltage 0,8 V by unit.
- Manual Charge of the batts, at C/5, manually stopped at 120% capacity
- New discharge, same conditions as first
- Try of delta peak charge at C/5, delta set -5 mV. Performed well : Tx pack 1820 mAh for 1700 nominal, Rx pack 840 mAh for 800 nominal.

The packs didn't get hot so everything is OK.

Here is my little experience.

Bye