If you upgrade to the MC-3000 just be aware of what you are getting to. I only thought I knew when I got one…. :person_facepalming:
A great charger no doubt. :+1: Much to complicated for me though. 
I love the UI of the Opus, but I feel like it’s worth the price point. I constantly get ghost battery indications (screen reads FULL after I take the battery out), bad voltage readings (full battery reads 0.2v), the fan has been giving me trouble for 2 years and just died, and one of the negative terminals snapped off so I’m left with 3 slots.
So I’ve heard that the newer Opus chargers have fixed these issues, but it makes me wonder if I should just invest in a higher priced charger
I don’t know if all the issues have been “fixed” or not on the OPUS. We discussed a bunch in this thread & a couple of others too.
My 3100 v2.2 works fine & I have no issues at all now that I upgraded the power supply.
Never had any issues at all with the Lii 500… it is my favorite.
Good luck choosing.
I know this is an old old thread but I bought the 3400 ,and when I asked the seller from e-bay (rdna)told the difference was the “sofrtware”
That’s all he knew or told me I have had it a little over a year and the only issue I have had is the power source melted and the seller is sending me a new one under warranty
That LITEON is sold out, and my Opus V2.2 came with the KYT 12V 3A power supply.
Is there another power supply you can recommend for this charger? Will any old 12V >=4A power supply work better than the supplied supply, or are there characteristics I should be looking for, like that efficiency standard?
At the 7 second mark of the video shows the Opus BT-C3100 V2.2 Charger sparking electricity, yellow flashes at the input plug connection every time I plug in power using the included 12 Volt charger(also used another 12V charger which also is sparking). Tested the included charger with my multi-meter and the charger is only 12.3 Volts DC. Is this a FIRE HAZARD? None of my other battery chargers ever spark. Connected the charger through my OPTI-UPS Grounded Surge Protector so its not an outlet issue, which I also tested and works fine with other electronics.
Reading through this thead on Page 4 about the “…The Opus will draw more than 3A in peak current, in my test I measured 6A for nearly 0.02 second. Then 0A for 0.03 seconds, bringing the average below 3A.” and reviewer listed “Power adapter: DC 12V, 3.0A ( Output ), 100 – 240V, 50 / 60Hz ( Input ) ”
Short video:
Longer video
Plug the power adapter into the charger first, then the power supply to the wall.
Best I remember this was discussed in one of these threads. It is normal . Mine does it. If you plug the 12 V in before you do the main it (of course) won’t do it.
I have the vague recall that those sparks on connecting power are caused by lack of capacitors to handle the surge current — cheap design.
Anyone know more/better? It’s not unusual to see those sparks on a lot of electronics.
The sparks are actually caused by the high voltage smoothing capacitors, due to the high current while they’re filling. Ideally the power supply should have an inrush current limiter (usually NTC resistor) on the input to prevent this but not all of them do since it’s not mandatory.
http://lygte-info.dk/info/SMPS%20workings%20UK.html
Search for NTC.
As a normal procedure , for most of the chargers and power supplies, first insert the main power cable in the 110-220 V , and then connect the secondary to the charger , WITH NO BATTERIES INSERTED ! Somehow , this is common sense...
This won’t prevent the sparking since it has nothing to do with whether the output is connected to a load or not.
If the preventing is the problem , just leave the 12V plug in inserted in the battery charger , and connect and disconnect the main supply . As for me , I have the 12V or 5V input for chargers connected ALL the time , and the mains are connected and disconnected thru few wireless plugs in ,with a remote control , as is needed.., I do think that is an elegant and reliable solution (I'm using it for many years ). A professional power supply has the NTC resistor placed in series with the high voltage capacitors , in the main voltage area , so , problem solved...
Thanks ferongr for your informative link and appreciate the helpful not so common sense answers for us newbees…
Side by side comparisons with two BT-3400 v3.1’s and 8 fresh batteries.
The fans have cycled several times. I think they’re quiet.
Hello,
I just ordered a new BT-3400. I hope that it comes with some sort of upgraded power supply that Henry mentioned in those back and forth emails. If it does not, would anyone have a link to a recommended replacement? Lite-On or otherwise?
Also, is there a good source of replacement fans for this unit? I can go ahead and buy the PS and fans now for future use.
You can get the replacement fans from gearbest for like 2 dollars or less. I got one just incase. I’ve had my opus for about 18 months roughly. And it’s used almost 24 hours a day I go to recycle bins and strip tool and laptop packs on top of 3 tomo power banks used daily and my flashlight at work and my vape units. There are batteries always waiting to be charged. Only had a couple issues with the opus. One was the power supply only when doing 4 batteries at 1 amp when they are low voltage it would reset and go to the default 500ma. The first power supply recommended before the lite on was supernight I believe 12 volt 5 amp. Never had a issue with that again. Never have had a fan issue. My opus froze one time and overcharged my batteries to 4.5 volts when I caught it. Discharged them instantly in a Fet driver flashligjt then did a capacity test. Didn’t damage the batteries. All my batteries have a label with the capacity and date last tested. Once a year they all get retested. I plan on buying a second opus. For the money it can’t be beat in my opinion. My unit undercharges slightly. It is .7 volts off. 4.2 on my opus is 4.13 on my dmm. My xstar and lii chargers go between 4.17-4.21. I’m fine with 4.13 honestly. Easier on the batteries. And only about 80 to 100mah short of completely full. It will help the batteries last longer. I have so many batteries a lot sit for long periods of time before being used. Sometimes you get lucky at the recycle bins. Example about 6 months ago. One bin had a couple packs I got about 20, Samsung 20r batteries all testing above 2000mah. A few good runs like thst batteries pile up. Not to mention all the laptop packs that only had 1 cell go bad all the rest perfect. It’s to the point if a cell is below 1800mah it goes back to recycling
Speed4goal,
Thanks for the boost of confidence in the opus. I own 3 LaCrosse 700s, 2 Xtar VP2s, an Ambient Weather 3100(opus clone) v2.1 and now the 3400 3.1 and Lii-500. I bought these last 2 mainly for lion batteries so I was quite interested in the upgrades to the 3400. Not sure if I’m ready for the MC 3000.
mine use to undercharge , it's wasn't really undercharging it was more like reading the voltage lower than it actually is , to make it read more accurate I desolderd the j1 bridge on the mother board , now it reads the same as my fluke DMM & it charges to 4.2.
Im still on my original fan , it made a funny noise once ,I just gently taped the fan casing with my finger and the funny squeeling noise stopped & it's never done it again, mine is the 3100 v2.2.
Zoom in and look at about the 3 o’clock position near the big black circle , desolder the bridge.