Opus BT-C3100 2.2-Comparison-New and Exchanged.

[Gauss163]

For those that may be confused,,,someone posted this:

"What did you experience with 3.1V vs. 2.8V discharge termination that made the cells appear better?"

I am not sure what he is talking about!! BOTH Opus chargers I had, the one now and the one I returned, are BT-C3100 2.2 and they BOTH discharge @ 2.8v.

Below is the comment in context:

I think the newer version[3.1] may be better for the batteries, especially protected ones. This is based what I have experienced and noticed after several discharges to 2.8V With some of my batteries.I know what the specs say, but Opus may have another reason for moving up the discharge to 3.0/3.1v besides that they were tripping protected batteries? [...]

What did you experience with 3.1V vs. 2.8V discharge termination that made the cells appear better?

I just report my experiences. Makes no difference what rdana says and what should or what should not happen.

My question meant: what did you "experience" that led you to write "I think the newer version[3.1] may be better for the batteries...". Perhaps you have discovered something that could be of general interest. But it is not clear what that is.

 

[Nev]

Another thing you could do is get the BT-C3400 V3.1. Its discharge terminates @ 3.1v instead of 2.8V like my BT-C3100 2.2.

The only place I see it is on Fleabay! $9 more than what I paid for mine.

http://www.ebay.com/itm/BT-C3400-V3...-ion-AA-AAA-NiMH-18650-BT-C3100-/331325504524

I've been looking for the version 3 but it seems very hard to find ,eBay USA seems to be the only place but it's about $70 with shipping to the uk.

 

[Nev]

Gear best has them for about £26 but it's version 2.2 , I'm just wondering why the version 3 is so hard to find ,is it obsolete now?
From what I've read am I right in thinking v3 has the updated power supply which make the mha figures better?

 

[HKJ]

Why go for V3, the higher termination voltage will give larger fault on capacity measurement?
With V2 it might trip protection on a few very old cells, but they would also have problems in a flashlight.

 

[Gauss163]

It's not clear how widespread the problem is. Was the Opus tripping UVP (undervoltage protection) only with high current on (old) cells with high IR, or is it possible that the problem was more widespread, e.g. some popular rewrappers used protection circuits with unusually high UVP? If it wasn't a widespread problem, then this "feature" may merely be a marketing ploy to differentiate rdana's version.

In any case, I think this is the wrong way to fix it. Instead, the Opus should be fixed to gracefully handle abnormal discharge termination so that it retains the test results and, further, provides an option to resume the discharge (useful if you accidentally knock loose a cell when inserting another). This makes much more sense than the kludge of raising the discharge termination voltage to 3.1V.

 

[markr6]

I think this is just what you get in the days of "disposable" electronics, especially at $30. Mine works fine, someone else's doesn't. Unfortunately it's the same with a $50,000 BMW...someone drives theirs for 15 years and loves it while another person runs into a problem at 1,000 miles and calls it a "POS! Worst car ever!"

Feel free to flame me for that apples to banana comparison

 

[Nev]

Why go for V3, the higher termination voltage will give larger fault on capacity measurement?
With V2 it might trip protection on a few very old cells, but they would also have problems in a flashlight.

Hello HKJ,
Is the power supply better on the v3 ? I will be using it at 240 volts (uk)
In your opinion is the v2 still a good charger for both nmh & lithium ?

 

[ven]

Not HKJ but the v2.2 is still a great charger, not had any power issues with all 4 bays loaded up at 1a. iirc some issues were with the earlier version, the v2.2 did put the power pack issue right.

The v3 as said has a 3.1v cut off, apparently due to some cells(older probably poor quality)tripping out.

For a decent enough do it all charger at a pretty cheap cost, the opus is hard to beat..............still!

 

[Nev]

Thanks ven.

 

[HKJ]

It's not clear how widespread the problem is. Was the Opus tripping UVP (undervoltage protection) only with high current on (old) cells with high IR, or is it possible that the problem was more widespread, e.g. some popular rewrappers used protection circuits with unusually high UVP?

Typical protection trips at 2.5 volt or lower and has less than 0.2V across when it trips.
That will not usual trip at 3A discharge current.

Is the power supply better on the v3 ? I will be using it at 240 volts (uk)
In your opinion is the v2 still a good charger for both nmh & lithium ?

Sorry, but I have not seen the V3.
The current V2 is good enough with the power supply.

 

[Gauss163]

Typical protection trips at 2.5 volt or lower and has less than 0.2V across when it trips.
That will not usual trip at 3A discharge current

Many protection circuits offer a wide range for configuration of UVP. So, as I said, it is possible that some rewrapper chose an unusally high value (or possibly some low quality versions have poor UVP implementation). But given that there are so few reports of this problem, it is unlikely we have enough data to figure out what is the true culprit.

 

[HKJ]

Many protection circuits offer a wide range for configuration of UVP. So, as I said, it is possible that some rewrapper chose an unusally high value (or possibly some low quality versions have poor UVP implementation). But given that there are so few reports of this problem, it is unlikely we have enough data to figure out what is the true culprit.

I have tested some protection LiIon batteries and I have never tripped any due to under voltage protection when I discharge to 2.8 volt, only a few due to over current.
That brings my back to my original complain about this: Wrong measurement on many cells, most modern cells has capacity below 3.1V

 

[Gauss163]

I have tested some protection LiIon batteries and I have never tripped any due to under voltage protection when I discharge to 2.8 volt, only a few due to over current.

But that's a bit of an apples vs oranges comparison, because your discharge algorithm differs from that used by the Opus (or did you refer to the Opus?) If you still have the Opus, why don't you do some definitive tests using the Opus. They would make nice additions to your reviews.

Regarding UVP configuration, e.g. the Seiko S-8261 has options for UVP between 2.000-3.000V, in 10mV steps, with ±50 mV accuracy, and 3 selections of delay times: 36, 144, and 290ms. So there is a wide range of possible UVP configurations.

That brings my back to my original complain about this: Wrong measurement on many cells, most modern cells has capacity below 3.1V

Yes, I agree that is a valid concern in some contexts. As I said, I think the change made in the C3400/V3 was a rather kludgey workaround for inadvertent UVP tripping

 

[HKJ]

But that's a bit of an apples vs oranges comparison, because your discharge algorithm differs from that used by the Opus (or did you refer to the Opus?) If you still have the Opus, why don't you do some definitive tests using the Opus. They would make nice additions to your reviews.

There is no definitive test, but it is well know that the Opus discharge with 2.5 to 3A pwm, this means the result will not be worse than a constant 3A current. For the cell below I would expect about 200mA less capacity with a 3.1V termination.

Regarding UVP configuration, e.g. the Seiko S-8261 has options for UVP between 2.000-3.000V, in 10mV steps, with ±50 mV accuracy, and 3 selections of delay times: 36, 144, and 290ms. So there is a wide range of possible UVP configurations.

I know.

 

[Gauss163]

There is no definitive test, but it is well know that the Opus discharge with 2.5 to 3A pwm, this means the result will not be worse than a constant 3A current. For the cell below I would expect about 200mA less capacity with a 3.1V termination. [...]

I meant UVP test, not capacity test. I agree on capacity.

 

[Capolini]

DISCHARGE/CAPACITY RESULTS

Device: NEW Opus BT-C3100 2.2

Battery:Samsung INR18650 30Q- FT-3000mAh

Purchased:November 27th,2016

Discharged @ 1amp

Cycles:5

Four slot average:2925mAh-HKJ-2884mAh-My Opus results are 1.5% higher than HKJ.

HKJ Tested:2884Mah for FT version
___________________________________________________________________________________________________________________________________________________________


DISCHARGE/CAPACITY RESULTS

Device: NEW Opus BT-C3100 2.2

Battery:Samsung INR18650 30Q-BT-3000mAh

Purchased:March 27,2017

Discharged @ 1amp

Cycles:1-Brand new-First cycle for this capacity test.

Four Slot Average:2910mAh. Although it is a BT and Not a FT which is the only one HKJ tested, it is 0.9% higher than HKJ[2884mAh].:thumbsup:
_________________________________________________________________________________________________________________________________
As you can see they are very close. The OLDER[4+Months] FT 30Q have a Four slot average of 2925mAh and the BT'S have a Four slot average of 2910mAh

 

[Capolini]

DISCHARGE/CAPACITY RESULTS

Device: NEW Opus BT-C3100 2.2

Battery:Xtar 26650 4000mAh Unprotected

Purchased:January 8,2014 *Only used it until January 7,2015 when I sold the light*

Discharged @ 1amp

Cycles:~80 to 100

HKJ- Discharged @ 1Amp-4267mAh

Capolini Discharged @ 1Amp-4332mah

 

[seanspotatobusiness]

Re: BACK TO BASICS-SIMPLE,EFFICIENT AND DURABLE!

Incidentally, could anyone tell me whether this charger needs each bay to be set up individually even if you want to do the exact same thing (e.g. 200 mA charge) with four batteries/cells at the same time? Thanks.

 

[tatasal]

Re: BACK TO BASICS-SIMPLE,EFFICIENT AND DURABLE!

Incidentally, could anyone tell me whether this charger needs each bay to be set up individually even if you want to do the exact same thing (e.g. 200 mA charge) with four batteries/cells at the same time? Thanks.

You can do from 1 to 4 bays together or individually, as desired.

 

[Capolini]

Re: BACK TO BASICS-SIMPLE,EFFICIENT AND DURABLE!

Just a Heads up for anyone who has this charger.

I had Three[3] FAILED attempts when I was doing the CHARGE/CYCLE test which is done for capacity results. All Three[3] failed shortly after the transition from Discharge to charge cycle. The charger briefly shut off, reset and then was defaulted to 500mAh charge current. This was w/ 4 X 18650 3400mAh discharging at 1 amp.Needless to say ALL capacity info. was lost.

This is in the process of being resolved on a thread on BLF that I am involved in. I gave HKJ detailed info and along w/ his knowledge he suspected that the Power Supply could not handle certain spikes in current. All Three times it happened slightly after transition from discharge to charge cycle when the batteries were ~ 2.80v! So I just got a 12v/5a power supply and I am doing tests. So far so good as Two tests have completed with Success!

The power supply cost only $6.99 shipped and was here[Suburbs of Philly] in 2 days from Portland, Oregon!!! USPS and the Ebay dealer get several :thumbsup:.