Dual 50V 5A H Bridge Speedo Heat Sink

[Guest]

Dual 50V 5A H Bridge Speedo Heat Sink

My post above should read that the low side FETs are insulated from the bar. The high side FETs are mounted without insulating pads.

[Guest]

Dual 50V 5A H Bridge Speedo Heat Sink

After further testing, I have noticed a tendency for my modification to cause shoot-through, probably because I have not been able to shorten the wire links enough to prevent a timing alteration of the FET switching.

[big_nipper]

Dual 50V 5A H Bridge Speedo Heat Sink

You can slow down the turn on and speed up the turn off by added another resistor and a diode in the MOSFET gate path.

[Guest]

Dual 50V 5A H Bridge Speedo Heat Sink

Unfortunately, I am no longer able to experiment, as the 5V data rail is short cct. This is probably because of lack of opto-isolation which allowed a large spike to damage the control circuitry when the shoot-through occurred.

[Guest]

Dual 50V 5A H Bridge Speedo Heat Sink

help!!!
I was being a bit careless and decided to attach my battery direct to the motor whilst the controller was still attached, anyway the FETs gave off lots of smoke and it no longer works at all. Can this be repaired???

[Mouldy]

Dual 50V 5A H Bridge Speedo Heat Sink

Ooops, You let out the magic smoke:sad:!

Either:
a) Buy new fets
b) Put the smoke back in

Regards
A bored Dave

[s8nsmum]

Dual 50V 5A H Bridge Speedo Heat Sink

Could anyone put up a pic or two of this mod? I am about to try it myself and want to see what every one else decided to do before I start.

[woody]

Dual 50V 5A H Bridge Speedo Heat Sink

You have mail Joseph.

[s8nsmum]

Dual 50V 5A H Bridge Speedo Heat Sink

Thanks Woody! Ill have a go at that next week sometime.