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OTHER: CNC Work Station - Controller - Servodrive

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Geckodrive:

Gecko says that it requires a 18 VDC to 80 VDC Power Supply.

Gecko says that the Power Supply voltage cannot be more than 5 V in excess of the Servomotor's rated voltage. Does this mean that all the motors must (should) have the same Rated Voltage? Or, that there be a couple of voltages available from the power supply(ies)? In addition to the +5VDC.

Gecko says that the maximum Servomotor output is 20 A.

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I have bought 4 only G340 20A, 80V PLL DC brush servodrive.

The Gecko servodrives G320 and G340 will accept 18VDC to 80VDC power supply.

The Gecko servodrives G320 and G340 have a current limit of 0 to 20A.

Watts = Volts * Amps = 80V * 20A = 1,600W. Does this mean that the Geckodrive will handle 1.600W?

Information on new G101G-Rex 6-axis motion controller

http://www.geckodrive.com/product.cfm?pid=17
http://www.geckodrive.com/photos/G101_Manual_Sept_3.pdf. Have hard copy.

Step Pulse Multiplier: For separate item [G910] see http://www.geckodrive.com/item.htbml?order_id=&item_id=G901

Posting to CNCzone ~ Gecko Forum:

I am starting the developing a cnc filament winder to produce composite helicopter blades. Some windings will be lengthwise (fast motion parallel to the X-axis) and other windings will be a wrapping about the X-axis (rotation of the A-axis with a slow advance along the X-axis).

The travel speed along the X-axis will be very different between the above two windings.

I am wondering;
1/ Will there be an advantage by using the G340 (or the G320 + G910) to drive the X-axis servomotor and thereby utilize the step pulse multiplier?
2/ Also, it is feasible to have remote electrical switching of the 'Multiplier Header'; either by a manual selector switch or by g-code at the start of each new winding run? Or, will some of the trimpots have to be changed at the same time?

Or is it just dumb idea?

Reply from ger21

The ONLY reason to use the G340 is if your computer can't output steps fast enough for the G320. ANd, no, you can't change it with g-code.

Notes and Questions:

When an error occurs at one servo, does the ERROR/RESET (terminal #5) shut down the other terminals? In other words, does it stop the total system?

Lots of questions and answers on Gecko - http://www.cnczone.com/forums/archive/index.php/f-31.html

Picture of the inside of the Geckodrive G320 Step and Direction Servo Drive

The gecko is counting pules coming in from the computer (Mach3) and the encoder, It then compares them and adjusts the step pulse waveform accordingly. The computer (Mach3) does not know what is going on at the motor until the count difference become large enough to send an error signal to it.

Current Limit: The current limit trimpot sets maximum current the motor is permitted to have. This appears to mean that larger motors could be used but they would be heavier and more expensive than necessary.

The Gecko Step Motor Drives require a small capacitor across the power terminals 1 and 2 [see Power Supplies (59.4K)]. I suspect that the Brush Servodrives will also.

The Gecko wants a digital quadrature TTL output type encoder that operates on a single +5VDC power supplt. It should be at least a 200 line encoder. Gecko does not stipulate whether the encoder should be Incremental or Absolute. Will an Absolute encoder work or not?

CNCzone ~ Ger21 ~ Ken, if you want (or need) to run at 45Khz, you should have at least a 2Ghz PC. Art recommends using the 25Khz whenever possible, and not using the faster speeds (35,45) uness you need to.

Rutex:

Bigger than Gecko. Costs more than Gecko. Rutex makes driver for brushless servo motors, which Gecko does not.

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Last Revised: May 22, 2007