SkyRC — IFA 2014 — MC3000 charger-analyzer

[skid00skid00]

Are you sure negative contact knows whether it was pulled by finger or by battery?

With 21700 and 26650 batteries, the negative terminal can be bent by the battery, which contacts the terminal at the top of the terminal.

By using a finger, you can pull the terminal back from the bottom of the terminal, lessening the bending force on the terminal.

A healthy dose of DeoxIT on the sliding surfaces also helps!

 

[Thoraldus]

Are you sure negative contact knows whether it was pulled by finger or by battery?

I guess it depends on how much metal you scrape/gouge out over time. ;-)

 

[-Archie-]

By using a finger, you can pull the terminal back from the bottom of the terminal, lessening the bending force on the terminal.

Half-second reduction of bending force, followed by several hours of spring-loaded state?

 

[-Archie-]

I guess it depends on how much metal you scrape/gouge out over time. ;-)

I beliveve it's thick enough to outlast the rest of charger's components.

 

[Thoraldus]

I believe it's thick enough to outlast the rest of charger's components.

Sure, if it were solid metal, but from the images I've seen above it appears to be plated. I could be wrong, but some of those images showing wear/corrosion have me wondering.

 

[Thoraldus]

With 21700 and 26650 batteries, the negative terminal can be bent by the battery, which contacts the terminal at the top of the terminal.

By using a finger, you can pull the terminal back from the bottom of the terminal, lessening the bending force on the terminal.

A healthy dose of DeoxIT on the sliding surfaces also helps!

Yes, I noticed that today when charging some 26650's

 

[mactavish]

I use my fingers as a tool, instead of the battery, to pull the sliders. Helps protect the battery wraps a bit. Not specific to this charger, but all the ones with sliders. I too ended up using DeOxit Gold as a slider lube.

 

[skid00skid00]

Half-second reduction of bending force, followed by several hours of spring-loaded state?

Some people just like to argue, others have to have the last word, and some people over/underthink things.

Static forces are *always* less than dynamic. In the case of this charger, there's a very large difference.

 

[-Archie-]

Some people just like to argue, others have to have the last word, and some people over/underthink things.

Yes, I see.

 

[Thoraldus]

I use my fingers as a tool, instead of the battery, to pull the sliders. Helps protect the battery wraps a bit. Not specific to this charger, but all the ones with sliders. I too ended up using DeOxit Gold as a slider lube.

If I remember correctly from a tear-down video of the MC3000, the slider mechanism is purely mechanical in function. The circuit connection is a thick wire soldered to the slider. (see image below - black wires) Given that I think I will use a Silicone Grease lubricant to remove the friction in the sliders.

 

[-Archie-]

Silicone grease is typically considered not optimal for metal-metal friction pairs, but still can be used. Are you sure factory-supplied grease is not sufficient? In my case, there's no need to add or replace it.

 

[Thoraldus]

I use my fingers as a tool, instead of the battery, to pull the sliders. Helps protect the battery wraps a bit. Not specific to this charger, but all the ones with sliders. I too ended up using DeOxit Gold as a slider lube.

Silicone grease is typically considered not optimal for metal-metal friction pairs, but still can be used. Are you sure factory-supplied grease is not sufficient? In my case, there's no need to add or replace it.

Yes, White Lithium might be better. Unfortunately the factory must have run out of lubricant when my MC3000 was manufactured, the sliders are dry as a bone. ;-(

 

[-Archie-]

That's interesting! Seems like quality control failure to me. Of course you'll need to lubricate it then.

 

[Thoraldus]

I use my fingers as a tool, instead of the battery, to pull the sliders. Helps protect the battery wraps a bit. Not specific to this charger, but all the ones with sliders. I too ended up using DeOxit Gold as a slider lube.

That's interesting! Seems like quality control failure to me. Of course you'll need to lubricate it then.

I sent off a note to SKYRC asking what they recommend and if white lithium grease is OK. ;-)

 

[mactavish]

I asked the LUBE question awhile ago and there was some good responses.

https://www.candlepowerforums.com/v...ger-analyzer&p=5429442&viewfull=1#post5429442

 

[Thoraldus]

I use my fingers as a tool, instead of the battery, to pull the sliders. Helps protect the battery wraps a bit. Not specific to this charger, but all the ones with sliders. I too ended up using DeOxit Gold as a slider lube.

I asked the LUBE question awhile ago and there was some good responses.

https://www.candlepowerforums.com/v...ger-analyzer&p=5429442&viewfull=1#post5429442

Yes, I read that and there seemed to be a misconception about how the negative terminal is connected to the circuit board. It does not connect through the supporting rail so any lubricant will not affect any IR measurements or charge/discharge current. Thankfully! ;-) Using DeoxIT on the slider rail for example is not going to improve any electrical characteristics of the charger. ;-)

 

[-Archie-]

Yes, I read that and there seemed to be a misconception about how the negative terminal is connected to the circuit board. It does not connect through the supporting rail so any lubricant will not affect any IR measurements or charge/discharge current. Thankfully! ;-)

Wait, are you certain about that? Maybe they've updated the hardware, but in my sample (bought shortly after initial release), the wires are soldered to the rails. It was one of reasons for me to do relatively heavy modding, including addition of the wires to bypass that unstable sliding contacts...

 

[skid00skid00]

If I remember correctly from a tear-down video of the MC3000, the slider mechanism is purely mechanical in function. The circuit connection is a thick wire soldered to the slider. (see image below - black wires) Given that I think I will use a Silicone Grease lubricant to remove the friction in the sliders.

I had mine apart last week, after my instant pot spewed bean soup all over it. My sliding, negative terminal did not have a wire attached. The circuit was completed thru the stationary rail that the slider contacts. I was concerned that the DeoxIT would affect amperage, but I got full programmed amperage into a 21700 and a 26500.

 

[mactavish]

Yes, I read that and there seemed to be a misconception about how the negative terminal is connected to the circuit board. It does not connect through the supporting rail so any lubricant will not affect any IR measurements or charge/discharge current. Thankfully! ;-) Using DeoxIT on the slider rail for example is not going to improve any electrical characteristics of the charger. ;-)

I was just looking to use a "proper" lube so my slides would move more easily. Not looking to "improve", but make sure the lube was not going to cause a problem. DeOxit seems the best choice of the 3 I listed, as I have them.

 

[-Archie-]

Thoraldus, I've viewed the previous page carefully: the picture you've attached explicitly shows the wires soldered to the rails. What makes you believe there's a version of MC3000 with different design?