Increasing G320/340 and G-rex current capacity

[crazyman]

Can this be done?
And how?
I was think maybe all that is needed was to replace the Driver FETs to higher current ones to carry the extra current. If it is that simple then you may also need to solder on some higher gauge wire than the PCB has to ensure no traces burnuo

What actually is the current capacity for the Grex? (It is not mentioned on the Gecko website.)

[Evodyne]

The GRex feeds command pulses to the drives and does not carry any high current. It is the drives you would need to modify. But even without knowing all involved I can tell you it would require more than just changing the MOSFETs. Remember, the drives also sense current as part of their operation. Were you to pass more current through, this circuitry would likely be overdriven. To keep this from happening you would need to modify the sensing circuitry as well.

Probably more feasible would be a daughter board carrying identical MOSFETs to those on the 320. These would be connected to be electrically parallel (without routing throught the 320's sensing circuity) and would be driven off the same (or a buffered version) of the 320's drive signals. So the 320 wouldn't know anything was different, but it would be supplying 1/2 the current of a larger total package. Keep in mind this is all supposition, just a guess on my part as to how one might begin to accomplish such a thing.

Evodyne

[DennisCNC]

^^ I have been woundering the same thing about transistors. If they will perform normal in parallel. Time to Google.

[DennisCNC]

Take a look at this:
Fets

Number five on the page.

Maybe you can make a 60 Amp MegaGecko?

[ger21]

You can use the 40A Rutex drives with a G-rex