Used my new x12 to charge the 10s11p pack and was good. Went for my 1st ride with it and it feels same as 12 cannot feel the difference.
Charged again and was running fine at 10amps. Decided to increase to 15amps which is well within the specs of x12 and the pack and the x12 made a flash and snap inside…its toast. inquiring about warranty but its a $300 disposable at this point. I really liked how it worked but if no replacement coming I will not buy another 
Glad to hear the 10s11p pack was working. Sorry about the x12 though. Higher voltage balance chargers are tricky to find and a bit expensive.
Which input voltage did you supply to the X12? From which source?
Its a 48v dc supply and was set to 50v. Its rated at 10amps. I think when I asked the x12 to do 15a it pulled the PS down and the x12 freaked out trying to keep up. I should not have went that far but it should have errored and not blew up. I think something was on the edge before it blew because the current set to 10amps was jumping around. Maybe the dc supply is crappy but I never looked at it on a scope. Maybe it has spikes that killed the input mosfets or whatever is on the input. If you connect anything there now its a big spark! It was a sad day
Yeah, maybe a bit weak…
The 10S battery when full will need 42V, at 15A, thats 630W…
So input at 48V you’ll need 15A or more including losses…
Although the X12 should have protection against that…
With the supply you describe, 10A for a 10S battery is really the max you should go, just for the future 
Yes agree I pushed too far. Silly the $300 x12 with all its smarts inside just popped.
If you want a more beefy supply, buying used Cellphone Tower Mainframe PSUs is a good option (at least in germany)
You get 48V 2000W for 60 Euros:
… or 6000W for the same price haha
Needs 2x 230V input though
I am thinking that what really was the problem was my dc power supply. I pushed it past its current and it likely sent unfiltered pwm volatge to the x12 which would have big spikes enough to kill the mosfet…my bad.