Review of / Measurement on 4Sevens Single Bay Charger V1

[HKJ]

Re: Review of / Measurement on 4Sevens Single Bay Charger

I'm kind of confused. So the over current charge can happen when using the included AC plug or does it only happen when using the car adapter?

With either of them, but USB is probably safe.

 

[BoarHunter]

Re: Review of / Measurement on 4Sevens Single Bay Charger

With either of them, but USB is probably safe.

Did you open this charger to get an idea of its circuit, identify the components ? No need to draw a detailed circuit diagram but from the main component, one get get a good idea. Does it use a microcontroller or special CC/CV chips ?

 

[badtziscool]

Re: Review of / Measurement on 4Sevens Single Bay Charger

With either of them, but USB is probably safe.

So even though the wall adaptor is rated at 1A, it can put out more current than that?

 

[HKJ]

Re: Review of / Measurement on 4Sevens Single Bay Charger

Did you open this charger to get an idea of its circuit, identify the components ? No need to draw a detailed circuit diagram but from the main component, one get get a good idea. Does it use a microcontroller or special CC/CV chips ?

No, there are no visible screws (They are probably under the rubber feets). I am convinced that it uses a microcontroller, both because of the saw tooth in the charge curve, but also because the lockup looks like something a microcontroller would do.

So even though the wall adaptor is rated at 1A, it can put out more current than that?

The charger has a buck converter to reduce the 12V to charge current/voltage, this will just about double the current.

I also has a unconfirmed guess that this converter is some of the reason for the lockup. When the battery is disconnected the charge voltage will for a short period increase to 12 volt, this may disturb the microprocessor enough to cause the lockup.

 

[sirimaxi]

Re: Review of / Measurement on 4Sevens Single Bay Charger

HKJ: Beeing you the one who discovered the issue...Are you in touch with 4Sevens to try the new version charger? Any clue of when this will happen? Thanks!

 

[HKJ]

Re: Review of / Measurement on 4Sevens Single Bay Charger

HKJ: Beeing you the one who discovered the issue...Are you in touch with 4Sevens to try the new version charger? Any clue of when this will happen? Thanks!

I told 4Sevens about the problem with the charger a few weeks before publishing this review, but I do not have any agreement about testing the fixed version.
When I get the fixed version, due to the general replacement of the chargers, I plan on verifying the above data and update the review.

I have no idea when the fixed charger will be available or when I will receive it.

 

[Battery Guy]

Re: Review of / Measurement on 4Sevens Single Bay Charger

HKJ

Very nice review. Thank you!

I like the concept of this charger, but would really like something that could charge more cells simultaneously. Is anyone aware of a multi-bay lithium-ion charger that has similar capabilities?

Cheers,
BG

 

[Got Lumens?]

Re: Review of / Measurement on 4Sevens Single Bay Charger

I've had mine open several times. Gimme a minute and I'll check the chips.

Its a 14 leg IC chip, ID on bottom, or MFG no writing. There is a load coil.

No, there are no visible screws (They are probably under the rubber feets). I am convinced that it uses a microcontroller, both because of the saw tooth in the charge curve, but also because the lockup looks like something a microcontroller would do.



The charger has a buck converter to reduce the 12V to charge current/voltage, this will just about double the current.

I also has a unconfirmed guess that this converter is some of the reason for the lockup. When the battery is disconnected the charge voltage will for a short period increase to 12 volt, this may disturb the microprocessor enough to cause the lockup.

 

[trooplewis]

Re: Review of / Measurement on 4Sevens Single Bay Charger

After spending the morning looking at Li-on chargers on ebay and getting confused, now I am more confused than ever. Should I just wait for the new version 4Sevens?

 

[HKJ]

Re: Review of / Measurement on 4Sevens Single Bay Charger

After spending the morning looking at Li-on chargers on ebay and getting confused, now I am more confused than ever. Should I just wait for the new version 4Sevens?

This is difficult to know before I have tested it, but I believe that it will be a very good charger.
A hobby charger can also be used, but if more difficult to work with. Pile has a very good charger, but I have not tested it.
CottonPickers are selling some charges here and they also works well, but does not include a cradle.

 

[sirimaxi]

Re: Review of / Measurement on 4Sevens Single Bay Charger

HKJ: Do you have V2 in your hands to test it? If yes, can you please tell me your first impressions? Thanks!!!!!

 

[HKJ]

Re: Review of / Measurement on 4Sevens Single Bay Charger

HKJ: Do you have V2 in your hands to test it? If yes, can you please tell me your first impressions? Thanks!!!!!

Not yet, shipping does take time.

 

[Bolster]

Re: Review of / Measurement on 4Sevens Single Bay Charger

I was about to ask if the new charger was identifiably different, but looking at this post says

"...it now has markings for negative and positive. Also there are two other noticeable improvements. The first is the larger sized battery contact indents, and the second is they have upgraded the sliding negative post to include a metal slide rail instead of plastic eliminating the wire that was required on version1. This change allows easier sliding of the post, helps eliminate binding, and assists in the loading and unloading of long cells..."

Also says v2 on the back label.

 

[HKJ]

Re: Review of / Measurement on 4Sevens Single Bay Charger

Added a text saying charger recalled (I will post a V2 review in a new thread).

Added a link to a list of external differences between V1 and V2 charger.

 

[sirimaxi]

Re: Review of / Measurement on 4Sevens Single Bay Charger

HKJ: So this means you received V2, no?

 

[HKJ]

Re: Review of / Measurement on 4Sevens Single Bay Charger

HKJ: So this means you received V2, no?

Exactly, you can see it if you follow the link to the comparison.

I plan on doing a full range of test on it, this will take some days.

 

[KLowD9x]

Re: Review of / Measurement on 4Sevens Single Bay Charger

I received my charger on Monday and I have a question:

Both of my 18650s (AW IMR and AW 2900mAh) get warm when charging at either 1A or .5A charge rates. I never noticed any change in temperature using the DSD charger. Should I be worried? They both come off of the charger at 4.19 volts.

 

[JA(me)S]

Re: Review of / Measurement on 4Sevens Single Bay Charger

I plan on doing a full range of test on it, this will take some days.

Thanks HKJ for being so thorough, I eagerly await the results...

- Jas.

 

[HKJ]

Re: Review of / Measurement on 4Sevens Single Bay Charger

Both of my 18650s (AW IMR and AW 2900mAh) get warm when charging at either 1A or .5A charge rates. I never noticed any change in temperature using the DSD charger. Should I be worried? They both come off of the charger at 4.19 volts.

The 4Sevens is using a higher charger current than the DSD, this might be the reason.

 

[HKJ]

Re: Review of / Measurement on 4Sevens Single Bay Charger

The V2 review is up.