Dear Peter, Would you explain detailed about why using the analog velocity input is better then pules/direction? Thank you!!
Howard > On Fri, 14 Mar 2008, Howard Chan wrote: > >> Date: Fri, 14 Mar 2008 00:06:03 +0800 >> From: Howard Chan <[EMAIL PROTECTED]> >> Reply-To: "Enhanced Machine Controller (EMC)" >> <emc-users@lists.sourceforge.net> >> To: "Enhanced Machine Controller (EMC)" >> <emc-users@lists.sourceforge.net> >> Subject: Re: [Emc-users] Can EMC2 support any 'AC Servo Motor'? >> >> Dear All, >> >> I am very happy, you propose some practical suggestions. I and my >> members take a meeting and decide that we will buy 5I20 control card and >> 7I33 analog servo amp interface. But there are problems, I would like >> to ask. Rayh said that EMC2 and Sanyo servo amp support step and >> direction. I try to find this method in the Sanyo manual and HAL >> handbook but I am not sure is it correct. > > The Sanyo amplifier also supports Analog velocity input (+-10V) > > This is the input you would use with the 5I20/7I33T > >> >> In page 45(3-13) of the Sanyo manual, it tells me that there are three >> types of command input pulse, Positive + Reverse pulse, Code + pulse >> train and 90 deg phase difference. In page 123(7-10), it shows me more >> detail information about them. I think that is it only ��Code + pulse >> train�� can be supported in the EMC2. If I want to use it type, should I >> buy 5I20 and 7I37 (Isolated Anything �� IO adapter)? > > You would be better of using the analog velocity input with EMC2 > > >> >> In the 7I37 manual, MOSFET outputs turn on in 2 uSec and off in 5 uSec >> but in the Sanyo manual page 123(7-10), the response time need at least >> or equal to 0.1 uSec. It means that 7I37 is not suitable this servo amp? > > The 7I37 is intended for power switching (relays solenoids etc) > Normally for step and direction you can use the 5I20 outputs directly, > or through a breakout board (7I42) These are not isolated but normally > the step/direction inputs on the amplifier are isolated so isolation > at the PC is not needed. > > But, for EMC2 I think you are better off with using the +-10V velocity > inputs of the amplifiers, rather than step/direction. > >> >> At last, according to their experience to create the machine > and > configure the EMC2, would you mind giving me some hits which > thing we >> should be take care. Thank you very much. >> >> Best regards, >> Howard >> >> >>> Hi Howard >>> >>> Glad to hear of your interest in EMC2. It is a great system for >>> students because it will allow you to experiment with most motion >>> control variables. >>> >>> The pdf at the link you posted includes a lot of sales pitch. It >>> appears to have been written and edited by someone with limited >>> motion control experience. They have very successfully blended >>> together at least three input signal types to maximize the apparent >>> value of their products. You will need to sort out most all of it to >>> get the system that will work for you. >>> >>> Sanyo lists three kinds of motion signals. They include analog >>> voltage, step and direction, and CANopen. EMC2 as it exists right >>> now can handle two of these, analog voltage, and step and direction. >>> We do NOT have serial drivers in our motion software that would >>> permit CANopen control. Hint -- Serial communication using CANopen >>> would be an excellent graduate student project. >>> >>> I'll expand just a bit on the two systems we do have for your use >>> right now. >>> >>> It looks like Step and Direction signals can be used with both the >>> stand alone amps and with the multi axis package. EMC2 produces >>> millions of step and direction signals every day. They are the >>> preferred motion signal for stepper motor powered systems. What this >>> drive does is make the servo motor look like a stepper motor if you >>> use this control signal. You will have a real advantage over >>> steppers because the motor's torque will not fall off as speed >>> increases but you will still see some cogging at low speeds. There >>> may also be an upper RPM limit, well below the max speed of the >>> motors unless the drive includes a pulse multiplier or you add an >>> external hardware work around. >>> >>> Permit me to do a bit of computation on this max rotational velocity >>> using step signals. If the supplied encoder is 2500 pulses per rev, >>> and the amp equates external steps one-to-one then you will need >>> 2500 pulses for each revolution. Let's imagine that your computer >>> can supply 30k pulses per second (PPS) using the EMC2. That >>> combination will allow 12 revolutions per second or 720 RPM. >>> >>> What is the maximum pulse speed you can expect from EMC2. Alex and I >>> were is a bit of a contest a while back and were able to get pulse >>> speeds of 75 to 90 thousand pulses per second. It may be that we >>> could get even faster speeds now that Jeff has added his rate >>> doubler. You can see that rotational speed is still somewhat >>> limited. At 90k PPS you would be limited to about 2100 RPM. >>> >>> The second type of speed signal that EMC2 can offer is an analog >>> signal. This could be pulse width or -10 tp +10 volt using a PC card >>> like Alex and Tom suggested. These analog signals have the advantage >>> of driving the motor to full speed and to constant velocity at low >>> speeds. Analog has the advantage of producing a real, closed loop >>> servo system. I would use this system even though it costs the price >>> of an extra computer board and requires a bit more care in wiring. >>> If you choose analog signals you must make certain the amps you >>> purchase allow you to connect those signals. Not all of the amps >>> listed do that. >>> >>> It looks like, although the pdf does not say so, that you will need >>> to use a Microsoft OS to tune the amps. Writing a Linux/EMC2 based >>> tuning software for these drives would also be a valuable student >>> project, if your school and discipline includes both hardware and >>> code writing. >>> >>> Good luck and welcome. >>> >>> Rayh >>> >>> >>> >>> --- [EMAIL PROTECTED] wrote: >>> >>> From: "Alex Joni" <[EMAIL PROTECTED]> >>> To: "Enhanced Machine Controller (EMC)" >>> <emc-users@lists.sourceforge.net> >>> Subject: Re: [Emc-users] Can EMC2 support any 'AC Servo Motor'? >>> Date: Wed, 12 Mar 2008 13:57:00 +0200 >>> >>> Hello, >>> >>> for what you want to accomplish you need a special motion control >>> board. >>> A list with supported hardware by emc2 can be found at: >>> http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?EMC2_Supported_Hardware >>> >>> Best regards, >>> Alex >>> >>> >>> ----- Original Message ----- >>> From: WF Chan >>> To: emc-users@lists.sourceforge.net >>> Sent: Wednesday, March 12, 2008 1:15 PM >>> Subject: [Emc-users] Can EMC2 support any 'AC Servo Motor'? >>> >>> >>> Dear All, >>> >>> I am a student. I will use a open platform system to control three >>> axis AC >>> Servo motors in my final year project(FYP). I searched a EMC2 in the >>> internet. It is base of the linux OS, it supports maximum 9 axis (very >>> powerful), GM code and graphics mode. It is very suitable for me to >>> do my >>> FYP. >>> >>> I have questions to ask all people: >>> 1. I must use AC Servo motors to do my project and I choose >>> SANMOTION R of >>> SANYO DENKI INC. Below is the user manual: >>> http://www.sanyo-denki.com/Data/Servo/catalogs/R_Ver3.pdf >>> In page 42(3-10), the pin 21 is the input control command which is >>> using >>> speed and torque value. >>> But I found in the HAL Handbook that it only support ��step pulse�� >>> to do >>> the control. >>> Is it menu that the EMC2 cannot support any AC servo motors?? >>> >>> Are there any people can help me or give me any suggestions how to >>> solve my >>> problem? >>> Thank you very much!! >>> >>> Best regards, >>> Howard >>> >>> >>> >>> Yahoo! ������������������������������! �������� >>> >>> >>> >>> ------------------------------------------------------------------------- >>> >>> This SF.net email is sponsored by: Microsoft >>> Defy all challenges. Microsoft(R) Visual Studio 2008. >>> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >>> >>> >>> >>> _______________________________________________ >>> Emc-users mailing list >>> Emc-users@lists.sourceforge.net >>> https://lists.sourceforge.net/lists/listinfo/emc-users >>> >>> >>> >>> >>> ------------------------------------------------------------------------- >>> >>> This SF.net email is sponsored by: Microsoft >>> Defy all challenges. Microsoft(R) Visual Studio 2008. >>> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >>> >>> _______________________________________________ >>> Emc-users mailing list >>> Emc-users@lists.sourceforge.net >>> https://lists.sourceforge.net/lists/listinfo/emc-users >>> >>> >>> ------------------------------------------------------------------------- >>> >>> This SF.net email is sponsored by: Microsoft >>> Defy all challenges. Microsoft(R) Visual Studio 2008. >>> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >>> _______________________________________________ >>> Emc-users mailing list >>> Emc-users@lists.sourceforge.net >>> https://lists.sourceforge.net/lists/listinfo/emc-users >>> >> >> >> >> ------------------------------------------------------------------------- >> >> This SF.net email is sponsored by: Microsoft >> Defy all challenges. Microsoft(R) Visual Studio 2008. >> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >> _______________________________________________ >> Emc-users mailing list >> Emc-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/emc-users >> > > Peter Wallace > Mesa Electronics > > (\__/) > (='.'=) This is Bunny. Copy and paste bunny into your > (")_(") signature to help him gain world domination. > ------------------------------------------------------------------------ > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > ------------------------------------------------------------------------ > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. 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