Stihl MSA200c battery charging issue after inactivity.

[kram]

14 hours ago, Mick Dempsey said:

TBH, I’ve rarely been happy with my efforts, it’s hit and miss if I get it at least as good as out the box.

I tend to throw a new one on long before it’s due, exasperated with poor cutting.

 

I didnt have anywhere decent to rest the camera so this is not a great example.. I did miss on the second tooth but no harm done to it.

 

Rotary grinder is good for these. Razor sharp and better than a file will get it. You only need to concentrate on the angle and let it work a couple seconds per tooth. Move it just a little so the bit wears evenly.

 

I hold the chain in one hand and also use that to advance the chain, it works really well but you could do it on a bench etc..

 

This is the only decent cordless option, Milwaukee M12BLROT.

https://www.powertoolworld.co.uk/milwaukee-m12-blrot-0-12v-brushless-rotary-tool-body-only

 

[kram]

26 minutes ago, openspaceman said:

I think the BMS has disconnected the battery, the small voltage you see is an ephemera of the bms connections. If so nothing will happen. If the battery was just flat the sudden rush of current would probably melt the wires you jumped the two batteries with, after all the 40V is 3 times what a car battery will zap if you touch the terminals together and a lithium ion battery has much lower internal resistance.

 

I've had similar on a cheap ( but useful) Ferrex 40V grinder battery. It was one cell out of the 10 that had failed. I made the mistake of not de soldering the BMS to get at it and struggled to pull the bad cell out from the nickel strips it was spot welded to. Knowing what I do now I would take it to our repair cafe with a new cell with solder tags ( about 6 quid) and get one of the electronics experts fit it. 

 

If I am right the other 19 cells will be good.

 

I recycle them by taping 4 together, adding a usb charger with type C charge port and protected usb output as little power packs.

 

Theres equal chance its just flat. A lot of packs do not have any fuse or mosfet capable of disconnecting the packs, often connections go directly to the tabs and the BMS is only there for charging and monitoring.

 

[Fatboy2017]

Good idea! I've got a Dremel and I think some 4mm rotary Granberg bits, I'll give it a go! Just got to get the battery up and running.

[Fatboy2017]

12 minutes ago, kram said:

 

Theres equal chance its just flat. A lot of packs do not have any fuse or mosfet capable of disconnecting the packs, often connections go directly to the tabs and the BMS is only there for charging and monitoring.

 

There doesn't look to be much in the way of BMS electronic circuit board in there, but it maybe behind the charge level lights and reset knob, I will strip it again and look for it. 

[kram]

I've learned, measure the bits because they are not always on size.

 

For the small Stihl chains, no one sells a 3.2mm bit specifically for chainsaws, however a worn 4mm bit, works very well.

Theres also 3.2mm bits in most diamond bit sets.

I got a load of them from amazon.

 

I did try with the fancy guides that screw on the tool but its much better free hand.

[Fatboy2017]

I have the guide which I got a few years ago, but decided I should spend more time on freehand filing and never used the guide! I think like you, for the 1/4 chain it would be better without.

[openspaceman]

53 minutes ago, Fatboy2017 said:

There doesn't look to be much in the way of BMS electronic circuit board in there, but it maybe behind the charge level lights and reset knob, I will strip it again and look for it. 

A google shows a thread on reddit for the ap300 battery which suggests the BMS may store a fault code that needs to be cleared after a repair, it maybe that Stihl have done a John Deere on this.

 

If @kram is right and there is no power control from the BMS via a MOSFET or IGBT then the BMS may communicate something to the charger to prevent charging and even after repair the battery may not work until this is reset.

[Mark_Skyland]

The stihl micro 1/4" chains sharpen up well with the 3.2mm, they are just a bit fiddly to do. A guide helps a lot as the file can bend if you put too much pressure on it. We don't offer a chain sharpening service as its just not worth the effort but I did used to sharpen our ms150 saw when we were still climbing. You just need to have a bit more finesse, or, if its hit something nasty just fck it in the bin.

 

Oregon has two types of 1/4", the standard uses a 4mm and the micro a 3.2mm.

 

This is the 4mm file size fitted to a few machines but mainly the older echo cs2511 with the 1.3mm var

Oregon ControlCut Chain - 25AP 1/4".050" - Skyland

SKYLANDEQUIPMENT.COM

---

Get your smallest jobs done just right. 25AP is lightweight, smooth chain, ideal for pruning — our Micro Chisel® cutters have small-radius working corners for excellent performance...

 

This is the 3.2mm file size for the ms150/151 and the newer cs2511 1.1mm bar

 

Oregon AdvanceCut Chain - 24AP 1.1mm - 1/4" - Skyland

SKYLANDEQUIPMENT.COM

---

The Oregon Advance Cut 24AP is a fast cutting low profile saw chain. File Needed - 3.2mm -  1/8" For Chainsaw Models - Stihl MS 151, MS 151 TC, MS 151 TC-E, MS 194 T, MS 194 TC-E...

 

 

 

[Fatboy2017]

23 minutes ago, openspaceman said:

A google shows a thread on reddit for the ap300 battery which suggests the BMS may store a fault code that needs to be cleared after a repair, it maybe that Stihl have done a John Deere on this.

 

If @kram is right and there is no power control from the BMS via a MOSFET or IGBT then the BMS may communicate something to the charger to prevent charging and even after repair the battery may not work until this is reset.

Any info on this Mark?

[kram]

46 minutes ago, Fatboy2017 said:

Any info on this Mark?

 

Old Makita LXT's were designed with three fusable links in the BMS, if you fully discharged them and tried on a normal charger, each attempt it would blow a link, three goes and done. However if you recovered the cells to normal it would charge fine but they never reset. After 3 blow, you have to replace the PCB with a knockoff one which are available from aliexpress etc quite cheapily.

 

I doubt knockoff Stihl PCB's are available.

You can get knockoff makita /dewalt/milwaukee etc.. battery sets cheap, this sort of thing.

 https://www.aliexpress.com/item/1005001577209628.html

 

 

Anyway heres a video of a AP300 being scrapped for parts. The pcb is by the lights and sealed, you cant get at it without destroying the pack.

 

Certainally not designed to be repaired!