Test/Review of Charger Opus BT-C3100 V2.1

[kosPap]

I have done the same, and I woill suggest a safety measure (I practice)
Cover the hole with a piece of blue masking tape or somethign like it.
When you sett he charger at 4.35, place the tape near the screen as a reminder.
After charging ALWAYS return the switch at 4.2V and cover with the tape.

 

[Climb14er]

Getting my BT-C3400 v3.1 charger later on... replacing my plug in and run Pila IBC charger.

What charge and discharge settings do you recommend, safe and approx 3 hour, give or take, for Panasonic Sanyo 18650 GA 3500 unprotected cells and Panasonic Sanyo Orbtronic 18650 3500 protected cells?

I've got some 2900 and 3100 Orbtronic 18650 protected cells also... just trying to get an idea what others are using.

 

[ven]

1a rate is fine, could use 1.5a if you wanted without any issue(can use up to 3.5a if available, but will take a few cycles off the cells life).

Up to 1a discharge is fine also, if you want a little more gentle discharge then 0.5a.

If i am charging more than 2 cells, i use the 1a rate regardless of 18650, be it high drain or ICR.

14500/16340 and 18350 i use 0.5a
18650 1a/1.5a
26650 2a

 

[Climb14er]

1a rate is fine, could use 1.5a if you wanted without any issue(can use up to 3.5a if available, but will take a few cycles off the cells life).

Up to 1a discharge is fine also, if you want a little more gentle discharge then 0.5a.

If i am charging more than 2 cells, i use the 1a rate regardless of 18650, be it high drain or ICR.

14500/16340 and 18350 i use 0.5a
18650 1a/1.5a
26650 2a

Excellent! Was thinking 1a on the charge and half that on the discharge.

 

[ven]

That will be fine and a little more gentle on the cell over 1a discharge. However it would be fine using either, it is a slow process so be warned..........Think on the second discharge I gave in, changed to charge and called it a day....literally :laughing:

 

[lojden]

Ordered "V2.2" from gearbest for $30, hope it is good

 

[markr6]

Ordered "V2.2" from gearbest for $30, hope it is good

Awesome how the best (IMO) charger of this class is one of the least expensive. Still using mine exclusively. Sure wish it would have come along before I purchased all the others!

 

[ven]

Ordered "V2.2" from gearbest for $30, hope it is good

Yes it is good, as with Mark nothing so far has come close for the money. I keep pondering the new xtar dragon, it costs 3 times as much and offers less charge rate options. Dont care for the probes really, novelty will wear off soon with them hanging around untidy. When my cell/s dont hold charge or last as long, i know resistance is built up too much and recycle time. No voltage read out when charging is not good for my needs either.............so right now, the v2.2 is still the charger for me, on day to day usage. Although it does a little too much singing and dancing for my needs, the skyRC mc3000 seems a more flexible option in the higher price category.

 

[Coolfx]

Hi,

I recently got 2 BT-c3100 v2.2 to test capacity or my powerwall project and I found the readings a bit weird.
I didn't noticed it first testing 2800-3000 mAh battery, given capacity of 1500 to 2800 seemed good, but I retested some old Samsung 26H I previously tested with a copy Imax b6 months ago (a lot were 2400-2500 on Imax) and now I got 2600-2700 at 1amp with these BT-C3100, more than the rated capacity of theses old cells.
I'm a bit confused about the readings of theses chargers, I checked the discharge current with my multimeter and got 0.78-0.9Amp fluctuating for 0.999-1Amp given at the charger screen.
Can I assume the charger discharge below the rating it's supposed but think he's in the range and give a false capacity ?
I haven't found anyone with this concern with v2.2.

 

[Gauss163]

@Coolfx Double check to make sure that your AC adapter has sufficient power. This was the source of similar problems in earlier versions.

 

[Coolfx]

I use the 3Amp provided adapter, EU version. It seems the problem with power adapters was during the charging, discharging isn't supposed to require a lot of current from AC.

 

[Gauss163]

Yes, the earlier problems were with charging, which I thought was your case but double-checking I see yours has to do with discharging. Possibly some discrepancy may be due to different termination voltages but I would not expect that much. How were you measuring the current? Possibly your meter might not yield accurate results for pulsed loads.

 

[UnknownVT]

I recently got 2 BT-c3100 v2.2 to test capacity or my powerwall project and I found the readings a bit weird.
I didn't noticed it first testing 2800-3000 mAh battery, given capacity of 1500 to 2800 seemed good, but I retested some old Samsung 26H I previously tested with a copy Imax b6 months ago (a lot were 2400-2500 on Imax) and now I got 2600-2700 at 1amp with these BT-C3100, more than the rated capacity of theses old cells.
I'm a bit confused about the readings of theses chargers, I checked the discharge current with my multimeter and got 0.78-0.9Amp fluctuating for 0.999-1Amp given at the charger screen.
Can I assume the charger discharge below the rating it's supposed but think he's in the range and give a false capacity ?
I haven't found anyone with this concern with v2.2.

I don't know how relevant this may be -
1) mine is a v2.1 and
2) way back in Sept/2014 -
I had one slot that gave significantly erroneous discharge readings, where the measurements were more than double the actual capacity when measured in another slot.

Please see Posts #55 and #59 (links) reported in this thread.

 

[Coolfx]

How were you measuring the current? Possibly your meter might not yield accurate results for pulsed loads.

Maybe my meter isn't accurate with pulse loads,I used my usual meter with 20Amp DC current capacity.

 

[Coolfx]

I don't know how relevant this may be -
1) mine is a v2.1 and
2) way back in Sept/2014 -
I had one slot that gave significantly erroneous discharge readings, where the measurements were more than double the actual capacity when measured in another slot.

Please see Posts #55 and #59 (links) reported in this thread.

Thx for your feedback, did you find a way to solve the problem on this channel ?
1)Readings seems consistant between channels and units here, it's more like both chargers are badly calibrated.
2)I don't really trust the capacity given by my old Imax b6 copy as it's cheap chinese stuff but I appear more realistic with 2400-2500 (and maybe too enthusiast ?) for a at least 5 years old 2600mAh battery.
3)According to the mesured discharge current (86% min of displayed 1Amp) and the given capacity of 2700+ it should be a real 2300+mAh which seems possible for theses cells. If someone have an idea to check the capacity let me know.
4) I also have a Skilhunt M4D charger, I will try to charge some cells discharged on the BT-C3100 and compare charge/discharge capacity.

 

[UnknownVT]

Thx for your feedback, did you find a way to solve the problem on this channel ?

No, never resolved. Got partial refund - so I have an Opus BT-C3100 V2.1 with 3 good channels (slot #1 one of the higher current ones is bad and I marked and just don't use it)

Since then I bought another (v2.1) when the price dropped.

My suggestion - if you are not satisfied with the charger - return for replacement or refund.

 

[bltkmt]

I have had this charger for a few months and love it so far. Have been slowly churning through my Eneloops, analyzing and charging them. I love being able to charge both battery chemistries without issue. Great tool!

 

[er84]

I bought this charger some days ago.

He is so great and seem to work find.

But when i plug the back power of charger i got some electrical sparks.

Should i be worried about that ?

 

[Bdm82]

I bought this charger some days ago.

He is so great and seem to work find.

But when i plug the back power of charger i got some electrical sparks.

Should i be worried about that ?

Can happen with dc adapters.
I find it best to plug the cord into the charger first, then the cord into the wall.
Great charger, though.

 

[er84]

Yes i will do it like this, seem more safe.

I also read its normal, its about the capacitor instant charging.