Running the revised G540

[dmauch]

I got an oportunity to test the revised g540 that has the trim pots mounted so that they can easily be adjusted without using a special insulated screw driver or tuning tool. The new trim pot is much easier to adjust without the danger of shorting something out.

The other revision Geckodrive made was adding a filter to the current sense lines. The reason for this mod was that the original concept of the g540 was to place the current setting resistor at the motor end connector. That way the motors could be connected to any cable and the current requirements would be met.
Some users were using inferior cable and this was casuing noise on the sense lines and thus the motors would run hotter than they should had they place the resistor at the G540 connector. But moving the resistor to the G540 end of the cable solved the problem but negated the benefit of the advantage of placing the resistor at the motor end.


I ran the prototype for about 8 hrs using a 48V power supply and various motors and various cable combinations. The motors all had their resistors at the motor side of the connector.
The new filtering worked well even on a cheap inferior cable. I observed a 28% reduction is motor temerature. On good cables with ferrite beads potteded into the cable the improvemt was a heathy 10.5%

A surprising side benefit that I noted was that running the same program resulted with the prototype case termperature of 112F. With and older D10 G540 the case termperature was 129F. I can only surmise that the G540 was running cooler because the motors were drawing less current due to the better filtering. In this case I blocked the air from my enclosures fan . Ambient terperature was 69F.
Dan Mauch
www.camtronics-cmnc.com

[doorknob]

Is there some external marking to distinguish the revised G540 from the earlier ones?

How does the pot adjustment look from the outside (as opposed to the earlier setup)?

[dmauch]

The one I tested was marked prototype. They are not out for sale yet.
The trim pot holes are in the same place but the pot itself is maybe a 1/4" blow the hole. Very easy to see.

Dan

Is there some external marking to distinguish the revised G540 from the earlier ones?

How does the pot adjustment look from the outside (as opposed to the earlier setup)?

[RPCElectronics]

That sucks. I just bought one direct from them for the full $299 price. I wish I would have known to wait on the newer version. I don't even need mine yet, I was just trying to gather up all of the parts. I am at least a few months away from even powering my G540 up.

I purchased the NEMA 23's on their site and was surprised that the wires were only about a foot long, so I planned to just put the DB9's on them, with the current setting resistor inside of that hood. I then brought some medium gauge ~18AWG multi-conductor cable from work to make three high-quality extension cables of about 8 feet each.

[dmauch]

It could be a couple months till they are availble. I would put the resistor in the connector on the G540 side of the cable.
In my testing I found that on some motors it didn't have that much different if you used a good cable. The difference was only 10F

Dan Mauch
Camtronics, inc. -- CNC with Dan Mauch

That sucks. I just bought one direct from them for the full $299 price. I wish I would have known to wait on the newer version. I don't even need mine yet, I was just trying to gather up all of the parts. I am at least a few months away from even powering my G540 up.

I purchased the NEMA 23's on their site and was surprised that the wires were only about a foot long, so I planned to just put the DB9's on them, with the current setting resistor inside of that hood. I then brought some medium gauge ~18AWG multi-conductor cable from work to make three high-quality extension cables of about 8 feet each.