48 cheap chinese controller upgrades

[jimmyhackers]

now im completely happy with my setup. i thought about adding more speed
in the form of another battery. simply adding another 12v battery to my existing 4 to make 60v. with a few controller mods
online i found some usefull articles but i thought id make my own to help other out there

my controller is rated at 48v 1000w or roughly 20amps. below is an overview of its guts.



the blue caps are the ones i figure need replacing. the two large and the 3 smaller ones. their ratings are 63v so possibbly they could hadle 5x12v batteries but there's nearly 5x13.8v = 69v available (almost), so they could go pop. im going bigger with the new ones in voltage and farads.

heres a closeup of the shunt wires and hopefully a readable mosfet



if you cant read they are hy1707, google is pretty useless at providing at datasheet but from what i can gather they are 75v and 80A max (please correct me if im wrong). so 60-70 volts shouldnt be a problem. with 15 of them (5 per phase i guess) i get more than enough current capacity. for reference at 48v the controller didnt get hot or even warm, it stayed stone cold. i figure they are pretty efficient at their job so i wont need to replace em, but i guess well see

i dont really think ill be touching the shunt wires yet. torque seems ample as it is at the moment. all ill end up doing is wasting more battery juice. i could possibly fry my mosfet or my board traces etc...

so yeah nothings beeen modded yet but a trip to maplins for about a fivers worth of caps and i might have myself a +35mph machine

ill let you know how the progress goes (with pics)

lets me know what you think.

p.s. i will be doing an oil cooled hub mod thread in time

 

[jimmyhackers]

huzzah. maplins finnally delivered. i went from 63v 470microfarad to 100v 1000microfarads and the three smallers went from 63v 220microfarads to 100v 470microfarads.

was an absolute ballache to desolder them (extra beefed up solder traces :s)... resorted to cutting the old ones out and redrilling new holes.

heres a pic of it all "crammed" in

.

i decided to go for higher farads for a reason "i think".... the new ones are 1000microfards "at" 100v but as ill be running them at closer to 60v and at 60v i dont think theyll have the same "1000microfard" capacity in them ,it should be proabably closer to the original 470microfards of the ones i removed.

eitherway...it works on 48v still, so i havnt broken anything. also i took it for a spin and could be placebo but i swear the mid range torque has picked up a little.

looks like im all set for 60v

 

[jimmyhackers]

60Vs is in preliminary...all is well, 32mph uphill 37mph on a flat and nearly 40mph downhill.

need to test more extensively before i get cocky. but so far so good

 

[jimmyhackers]

huzzah, 2 rides and 4 lipos discharged. all on my new 48-60v relay switching arrangement.

all is great. ill give rundown of my "findings"

i get about 3minutes of runtime per lipo at 60v and still can switch back to 48v when i run out of lipo juice. (could do with bigger lipos)

it appears that i can switch between 48v and 60v at full throttle without detrement to the relay, controller, motor etc. you can feel a little boost of torque when you switch between the two : )

from a standstill at 60v you can accelerate to 0-30 mph quicker than with 48v

however going from 30mph upto a max of 37 on a flat seems to take a while.

the controller stays cool and the motor gets warmish much like 48v. i used the full 60v for the full 3minutes my lipos can give on an uphill route and heat remains the same.

heres a pic of my "test" wiring and temporary carboard battery box.


i need to mount the switch on the handlebars, neaten up my wiring and colour in the carboard box black with felt tip
quite possibly put in the grippier cartridge pads into my brake shoes to up my braking with the new speed.

then shes good

 

[jimmyhackers]

thought id do a very crude circuit diagram on paint explaining the relay arrangement.



sorry had to re-edit this as it wasnt quite correct.

 

[jimmyhackers]

i have now welded a mount for my boost switch onto my handlebar.

heres a pic.


all is still good. been for another 2 rides and 4 lipos. no problems.

the new placement of the switch really helped me dial down when i use the extra voltage. meaning i still get about 3 minutes of life per lipo but i can space it out and use it a lot more strategically.