SkyRC — IFA 2014 — MC3000 charger-analyzer

[kreisl]

And a question for current owners - is there an option for just IR measurement without starting a program, or for that i have to upgrade to 1.04b?

current owners don't have that feature. in 1.04b the feature is present, just press STOP+UP button together, in TOV.

 

[DeJaVu]

I'm still rocking 62-65 degrees Celsius, discharging 4 Li-ion at 1A.

All I did was flip my fan and cut the grill out to reduce restriction.

Some of the other guys are doing stuff that still runs the charger near 85 Celsius and seems a lot less simple than what I did in 5 minutes.

Just my opinion, flip fan, cut grill, run way cooler, move on to a different problem.

Will definately do that in near future, even though i dont see myself discharging 4x1a at a time i still like my electronics cool, and cooler means longer service life.
Have this bad boy lying around
http://www.newegg.com/Product/Product.aspx?Item=N82E16835118057
So i even might scavenge the fans and go for the double turbine mod

All of my cables worked perfect with the charger untill I tried to provoke it with different USB sticks in the other ports. There seams to be some bugs in the PCLS that make the graph to freeze. Have no problems with other things in my USB ports.

Yep checks out, same behavior . Even tried disabling xHCI from bios as the intel USB 3.0 driver has been known to have problems with certain devices, but nothing changed.

current owners don't have that feature. in 1.04b the feature is present, just press STOP+UP button together, in TOV.

Thanks for the info.
BTW, youre on my "coal for christmass" list .
What happened with the flattop compatibility? Did you catch it and SKYRC didnt find it important enough to improve the positive terminals, or?

 

[kreisl]

All right, i've submitted the bug report re fw 1.04beita, hopefully 1.04 will be bug-free

Since all vendors only have stock of the charger with the upwards blowing fan, here a share of my personal mod, interesting information for early adopters who got the downwards blowing fan. Even if composed in instructional style/guide, i don't recommend doing this mod, because it may invalidate your warranty and you could damage the charger (electronics, wires, soldering, fan, plastic housing, plastic brackets, plastic threads, etc) in the process.

1. remove the 6 screws at the bottom side of the charger. the 4 rubber feet are attached to the plastic thru double-sided adhesive film. pull gently at a corner of a foot, hold the pulling force, lift that corner, the foot will slowly detach; be gentle, you don't want to tear the film. no tools needed, for the pulling/lifting use your finger nails. don't touch the film.
2. slowly lift the bottom case a centimeter: you'll see the wire of the fan. detach the wire (fan plug) from the PCB, gently. now you can separate the bottom case from the PCB.
3. take note to which side (left or right) the fan wire is going. when you reverse the fan, obviously the wire should go into the identical direction, towards the fan socket on the PCB. i'll call you dumb if you mess that part up.
4. a fan has 2 sides: the label side and the back side. since your fan is blowing downwards, your eyes are facing the back side of the fan. And you can see 2 plastic brackets holding the fan snugly in place. IMPORTANT: the brackets are fragile, they easily break off their base. And they will, if you are not gentle. Do not put any strain on the brackets. I warned you. This is the first and the last time that i have warned you about breaking off the brackets. one warning is enough.
5. you're also seeing some dried yellow glue at your fan and on the brackets. use a utility knife, make some appropriate cuts in de/thru de glue, then take your time and slowly remove the glue with finger or knife. it is easy enough to remove the glue, which is nice.
6. now you can finally lift out, gently, the fan. all glue gone, all clean? ok.
7. before putting the fan back, in reversed direction, we'll need a 0.7-1.3mm thick spacer in the 4 corners. without a spacer the fan rotor would touch the grille and produce extra noise. find something cute in your household, possibly some rubber, plastic, pad, not too hard, not too soft. for example you could cut out spacers from a jar rubber seal.
8. with the spacers in place, you'd notice that the fan is too high for the brackets to hold it securely: the brackets don't snap in anymore! so we can either mod the brackets or mod the fan.
9. mod the fan by making a very small chamfer at the fan edge where the brackets would grip/snap. doesn't need to be a "0° bevel" ("cut out"), a 45° bevel would do too. if you cut too much, too big a bevel, you'd introduce play, which would lead to a rattling fan. for making the chamfer i'd use a utility knife. files are a bit messy.
10. when you insert the fan with the spacer in place, don't push on the middle of the fan when seating the fan, or you will break the fan construction, it's a small fragile fan after all! the brackets should snap in, as best as possible. as you can see on the photos, the distance between the brackets is 32.90mm, and after this mod i am getting 33.55mm. in other words each bracket is suffering a strain of 0.325mm. That's not too bad actually because it means that the brackets prevent rattling in the sidewards direction too, not only in the air blow direction. But with strain comes deformation and a deformed fan frame will be the cause of noise produced by rotating fan blades touching the frame! Maybe Sky used yellow glue to eliminate rattling noise, vibrational noise originating from tolerances of the fan dimensions. Well, with my mod, i don't need any glue.
11. put everything back together, don't screw down the 6 screws tight (plastic threads!), vacuum your house, and enyoj the new air blow direction. upwards.

a mod brought to you by the squirrel. all copyright ©2016 k

 

[Albert_]

It's more difficult to find a DC fan rated at exactly at 15 VDC. Do you think a 15 VDC rating is necessary for a replacement fan?

From the pics it appears the stock fan is 30mm x 30mm x ~10mm? Is there some sort of CFM and RPM rating?

More common 12 VDC fans sometimes have a DC volts range rating related to CFM and RPM.

Plus other ratings

e.g.

Voltage rating = 12
Power current = 48 mA
Power consumption = 0.58
Speed = 9500 RPM
Air Flow = 5.5 CFM
Static Pressure = 0.15
Noise = 23.0 dB(A)
Curve = 1

 

[kreisl]

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[Albert_]

I'm not saying the stock fan needs a replacement. I was mainly wondering if for some reason you needed or wanted to replace the stock fan, such as the fan wearing out, too noisy, wanted more CFM, etc, would 15 volts become an issue?

I suspect it wouldn't and a 12 volt fan with a voltage range could be used as a replacement fan. I would need to measure the fan pins voltage output, mostly likely it's being powered directly or indirectly from the 15 volts psu input.

I was just asking as I usually look at all variables when trying to understand various types of equipment. That is one of the reasons why I was asking about the stock fan specifications, I just wanted to better understand it's cooling efficiency.

Temperature control has been an issue with all kinds of electronics, before the advent of PCs. PC cooling became an issue back when the first PCs were being developed and coming onto the market.

Here are some 12 volt fans from Digi-Key, I don't recall any selection for a 15 volt fan.

http://www.digikey.com/product-sear...t=0&page=1&quantity=0&ptm=0&fid=0&pageSize=25

By the way I like your write-up, has good pics, it covers most if not all details for a fan reversal.

 

[kreisl]

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[billcushman]

From the pics it appears the stock fan is 30mm x 30mm x ~10mm? Is there some sort of CFM and RPM rating?

The stock fan is 30x30x7mm. It is a JSL DC Brushless Fan manufactured by Jiang Shan Lai Electronics Co. Ltd. It is model #JDM3007S rated at 15V 0.10A.

 

[tjh]

Edit: Seeing as the post I was reply to was (deleted) I will go ahead and do the same.

 

[billcushman]

Albert, I purchased the following fan so I could examine a similar fan.

http://www.amazon.com/gp/product/B00MYNWWXE/?tag=cpf0b6-20

When I bought this fan it was about $8.00 on Amazon. It is available from Chinese sources for much less but I wanted in a 2 days. I tested the fan with a variable DC power supply. At 12 volts the current was 0.12A. At 15 volts the current was 0.14A. The fan was very quiet in free space and could be mounted with the rotor side down with no interference on my sample. I didn't put this fan in the MC3000. I didn't run any long term tests to see if it was OK a 15 volts continuouly.

 

[Albert_]

kreisl has noted there are no cooling issues with this charger. However there are posts by some users who have reversed the stock fan and or added fans to this charger.

I would need to first use and test the charger along with it's fan firmware control, to determine the charger's cooling efficiency.

Here's an article from the Sunon website I found interesting. Discusses in some detail "How to Select the Right Fan or Blower"

Perhaps it's not a practical method I would normally use, but does provide some insight into methods used by manufactures when engineering cooling for their equipment.

http://www.sunon.com/uFiles/file/03_products/07-Technology/004.pdf

 

[kreisl]

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[kreisl]

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[tjh]

Seeing as the posts I was replying to were deleted, I'll do the same.

 

[fnsooner]

Hey guys, is there a way to automatically discharge to a voltage of your choice? I am wanting to test the current draw of a couple of flashlights at different voltages, I.e., 4.00VDC, 3.75VDC AND 3.5VDC.

I have been setting the slots to storage or discharge and catching it on the way down.

In Advanced mode, when going to "discharge" there is an option of "target voltage" but I am rejected when trying to input anything into it.

No big deal if not. I am just trying to determine if I should quit looking. Thanks.

 

[tjh]

Hey guys, is there a way to automatically discharge to a voltage of your choice?

Page 21 of the user manual, last paragraph "CUT VOLT"

Short answer: Yes, this is one of the features of this most excellent charger.

 

[fnsooner]

Page 21 of the user manual, last paragraph "CUT VOLT"

Short answer: Yes, this is one of the features of this most excellent charger.

Thanks.:twothumbs

 

[kreisl]

charger can produce stable offline voltages, storage mode is limited to {3.65|3.66|…|3.99|4.00}V afaik, so for 3.5V the battery needs to be discharged with discharge mode CUT VOLT {2.50|2.51|…|3.64|3.65}V. set Zero as termination and -Zero for discharge reduce.

 

[Albert_]

I don't think I'll be replacing the stock fan.

However I would like to know it's CFM and RPM ratings.

For those interested in fans and cooling. Here are a couple of links I found to pdfs reguarding cooling fans.

http://www.sunon.com/uFiles/file/03...d/Sunon DC Brushless Fan & Blower_(190-E).pdf

http://www.sunon.com/tw/products/pdf/maglev.pdf

 

[DeJaVu]

Saying this is incorrect and misleading also. Feel free to make use of quotes.

There are no "high temperature problems" with the charger while discharging 4 LITHIUM-ION batteries at one amp.

I know which phenomenon you are referring too, the discharge load reduction implemented in the firmware if a max temperature is reached (for any reason), but that's not a bug or an issue or a problem but a feature. And that phenomenon cannot be observed with the currently available chargers anymore.

Feel free to call it "discharge load reduction observed in early chargers" but don't generalize and call it "cooling issues with the charger" or "high temperature problems". And if that is too long for you, then abbreviate it to DLROIEC.

From manufacturer standpoint it might be considered a "feature" , but from user standpoint it is an issue and the load reducing i consider a failsafe so the charger doesnt burst in flames.
As an example modern cpus come to mind, reducing frequency because of high heat is not a feature but a failsafe.
It dictates that cooling needs to be chacked for malfunctions or upgraded as it is not doing the proper job and the part isnt functioning at its manufacturer allowed full potential.
If they would have done proper testing(it really escapes me how can almost 2 years of development end up with such trivial error) on the charger before producing, they could have capped the 4x discharge at 0.8. Or even better produce it with fan facing up straight away, and this conversation wouldnt have even existed .
Dont get me started on non-protruding + flattop batteries not being detected unless you use a magnet or raise the battery.

Dont get me wrong, i still love it and is a one hell of a charger , with nothing that comes close to it in this form factor.
I would recommend it to anyone willing to spit the asked ammount.