Hi gearbest,
Is the fan issue for the current stock fixed? I.e if I buy now, would it still have the loud fan problem? Or the current stock had been retrofitted with the new fans that are quieter? Thanks.
What works for me, is that you can change the Mode of the bay to DIscharge Refresh (I think thats what its called) and then it works for me!
I still haven’t received my replacement fan so no evaluation from me yet.
Edit: got the replacement fan today. It is the same as the old fan with heavy grease in the bushing. The rotor still has a lot of angular play.
I’ll see how well it behaves over the next few days.
I was just reading over some of the previous posts and saw two issues.
First is the voltage reading high and the second is the fan issue.
Is now a bad time to purchase one of these chargers? Is a fixed version in the works?
(I'm trading my hobby charger and getting this charger, so I don't really want to downgrade)
Hi,
I still haven’t received the fixed/updated fan but I have another question…
I would like to charge a D type cell but by default it’s not possible with BT-C3100. I’ve found out that there’s an adapter available but unfortunatelly it does not ship to Poland 
Do you know if the adapter is available in some other webshop or do you know of any other way to charge D/R20 cells with as little hassle as possible? I did see this topic but that’s beyond my skills…
Best regards,
Crocodil
Great, that’s exactly what I need 
Thank you very much!
So far, so good. I swapped in the new fan which only takes minutes. It came with the little “grill” piece if you can call it that. I put it back together as it was originally. I have been testing 2 18650 cells at the 2 amp rate (1 amp discharge) and I haven’t heard the fan kick into turbo yet. In general, it is a lot quieter than before. No case rattles or vibration. I could smell the unit heating up though. I am trying NOT to burn up the unit. I will have to try running 4 cells in test mode next.
Has anyone checked the OPUS discharge test results against a hobby charger? I just received a hobby charger for Christmas and I'm seeing drastically lower capacities (testing at same 1A rate). I'm suspecting the OPUS to be fairly accurate and my hobby charger to be wrong.
-Garry
I have posted some pics somewhere around here in the forum the result of both discharge tests of my iCharger and Opus 2.1 and the result difference on the same cell was only 8 mAh. Perhaps your hobby charger is showing wrong readings?
Edit: It’s in post no. 182 of this thread…unfortunately some pics got deleted in that post when I deleted some pics in Photobucket. Didn’t know if you delete a photo in Photobucket, that photo posted somewhere also gets deleted.
Thanks. Confirms my suspicion. My hobby charger is giving me hundreds less mAh's. I calibrated the voltage reading at 4.20v. Not sure about the 3.00v end of discharge because the cell reads 3.45v +/- when the load is removed.
-Garry
My Accucel 6 also shows hundreds less mAh’s for my 18650’s than my Opus v2.1. It’s just as bad for NiMH batteries. I tested about 20 fresh-of-the charger year old Eneloops and they ranged from 1650mAh to 1760mAh. These were charged on 4 different smart chargers and I have a difficult time believing that 20 Eneloops charged on multiple chargers were all bad. Testing them on the Opus yielded more believable numbers, ranging from 1922mAh to 1980mAh.
My notes show that I discharged 2 Panasonic 3400’s that I bought this year and got 2967mAh and 2910mAh (discharged at 1A and fresh of the charger at 4.19v and 4.20v). Off the Opus they discharged to 3408mAh and 3308mAh. Tests were done 8/15 and 12/15 this year.
I don’t believe it’s a termination voltage issue with the hobby charger since there isn’t much left at the low end of the voltage scale.
I'd suggest that the voltage does terminate at 3 volts but rebounds to 3.45 as there is no longer a load on the cell. The difference is the voltage sag at whatever load you discharged the battery at. The higher the load the higher the voltage sag.
Your Opus’ results with both li-ion and nimh are very consistent and within a few mahs to my tests with my 2 Opus chargers, iCharger and C9000.
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Hmm. . . I know my charger is similar to the Accucel 6 except that it's rated 2A / 10w discharge. So are none of the inexpensive hobby chargers accurate for discharge testing? This really irritates me because I really only bought the hobby charger to do discharge tests! And I spent time to find one highly rated and purposely moved up from the bottom entry level units. (It's a Thunder AC680.)
Sorry for taking the thread off-topic.
-Garry
I just got a 3180 and 3215 reading on 2 very well used KeepPower 3400 18650 cells on the Opus.
I tend to believe this reading within a reasonable tolerance.
Count me as irritated too. My Accucel is good for tracking how my cells age but not how good they really are. It’s of course useful for other things but not what I really bought it for.
Does your charger terminate when charging NiMh’s? Mine definitely misses the termination signal so it’s useless for charging or refreshing my NiMh’s.
My Opus has yielded believable numbers based upon testing new cells, both lithium and NiMh.
I haven't tested NiMh's nor did I really plan to use it with them as I have other testers and have no multiple NiMh packs to test (yet). I'll PM you for further discussion on the Hobby Chargers as I don't want to pull this thread further off-topic.
-Garry