Gecko 540 and Resistor question

[SpeedsCustom]

Right now on my machine running a Gecko 540. I have three (3.3k) resistors installed on all axis. So I'm not at 100% efficiency as far as resistors go.

I have in the shop a few 3.6 K resistors. I tried to order 3.5 K but Mouser didn't have them (Still don't). I know the 540 will only output 3.5 Amps per axis. Will I severely damage anything with the 3.6 K resistors? I can't find the 3.5 K and I need to get the machine running.


Will I damage anything on the 540 or the steppers?


-Jason

[rowbare]

With the 3.3k ohm resistors you are down maybe 6% compared to 3.5k ohm resistors why risk it?

Is there room in the connector to add a second resistor? You could always add a second resistor in series to get to 3.5k, or you could hand select from a batch of 5% 3.3k resistors to get some that are at the high end of the tolerance range.

[acondit]

Jason,

I am with rowbare. I wouldn't risk damage to the G540 by using more resistance than Mariss recommends. I recall that Mariss said using no resistor (almost infinite resistance) results in the automatic power reduction failing to work.

Maybe Mariss will chime in and tell us what the effects of using 3.6K resistors would be.

Alan

[CarveOne]

If there is room for two resistors I would rather parallel two values that are relatively close together to give 3.5K ohms or just a little under 3.5K ohms. Two 6.8k in parallel will give 3.4K. 7.150K in parallel with 6.8K gives 3.485K.

CarveOne

[Mariss Freimanis]

You won't damage anything with a large resistor (>3.5K). You simply won't have standby current reduction and your motor will run hotter. Digikey has 3.48K 1% 1/4W resistors at $0.49 for 5 pieces (Digikey part number 3.48KXBK-ND).

Mariss

[SpeedsCustom]

Thanks Mariss!

Thanks everyone else for posting. I always used Mouser, so never checked Digi.

Thanks,

-Jason

[poordumbbastard]

Jason,

Did you ever figure out your EMC2 problem or is it still giving you fits?

I want to run the same setup you have but do not know if its a good idea since you have had so many problems.

Please let me know how your system is working now.

PDB

[SpeedsCustom]

Poor- I am going to be working on it this week. I have a new video card that came in that i'm about to install. I also want to get the 3.5 K resistors to make sure that I'm getting all the amps possible.


-Jason