Re: Advice on buying servos.
http://www.ebay.es/itm/CSDJ-02BX2-CS...cAAOSw0vBUl2gB
Thats what i have / the 400w/ and where i bought it from. And what i would recommend. Just check again for the details in the manual. You will not find anything better for the money.
Re: Advice on buying servos.
Quote:
Originally Posted by
Boyan Silyavski
Ahh, the AC does not have brushes. The DC servos with brushes are older motors with older drives that may need Voltage control +-10v, not pulse control. That could make things bad, as this type of controllers are expensive cause their only purpose is to retrofit old machines. Hence thats why i told you to search for drives that support Pulse and Direction
Thanks, sorry for being so dim about this - it's begging to make sense. Also many thanks for the links.
BTW. Apart from power, is there any difference between servo motors used for positioning ie x,y,z axis motors and servos used for spindles?
Re: Advice on buying servos.
Quote:
Originally Posted by
Agathon
Thanks, sorry for being so dim about this - it's begging to make sense. Also many thanks for the links.
BTW. Apart from power, is there any difference between servo motors used for positioning ie x,y,z axis motors and servos used for spindles?
Yes and No. Any servo motor rightly belted could serve for spindle. But then comes the RPM. The servos that are meant for spindles could spin at higher RPM and have slightly different curve. We are talking about typical motor that will be connected to BT30, etc spindle via belt. As Yes, you could gear up any servo motor but then you need bigger more expensive motor.
these are the servo spindle motors. they gto up to 15k rpm https://www.aliexpress.com/store/pro...809932059.html
Re: Advice on buying servos.
Quote:
Originally Posted by
Boyan Silyavski
Yes and No. Any servo motor rightly belted could serve for spindle. But then comes the RPM. The servos that are meant for spindles could spin at higher RPM and have slightly different curve. We are talking about typical motor that will be connected to BT30, etc spindle via belt. As Yes, you could gear up any servo motor but then you need bigger more expensive motor.
these are the servo spindle motors. they gto up to 15k rpm
https://www.aliexpress.com/store/pro...809932059.html
Thanks again. Not cheap then.
While I'm here. Am I right in thinking that the advantage of an absolute encoder over incremental is that the motor position is known after power-down?
Re: Advice on buying servos.
Yes, but there are different types of absolute. you have single turn and multi-turn, the name is self-explanatory.
Also, Absolute encoders have a much higher resolution than incremental.
Quote:
Originally Posted by
Agathon
Thanks again. Not cheap then.
While I'm here. Am I right in thinking that the advantage of an absolute encoder over incremental is that the motor position is known after power-down?
Re: Advice on buying servos.
Quote:
Originally Posted by
Gary
Yes, but there are different types of absolute. you have single turn and multi-turn, the name is self-explanatory.
Also, Absolute encoders have a much higher resolution than incremental.
Thanks. I notice that you have both DC brushless and AC servos on your website - what are the advantages and disadvantages?
Re: Advice on buying servos.
Quote:
Originally Posted by
Agathon
Thanks again. Not cheap then.
Servo controller for me is a must for a metal working machine, a heavy gantry router or a high precision machine for miniature machining, industrial production machine that needs to be fast as possible For all else a stepper will do just fine job.
Re: Advice on buying servos.
Quote:
Originally Posted by
Boyan Silyavski
Servo controller for me is a must for a metal working machine, a heavy gantry router or a high precision machine for miniature machining, industrial production machine that needs to be fast as possible For all else a stepper will do just fine job.
What I really meant was that servos for spindles weren't cheap. I'm a great believer in "getting what you pay for". I can live without a servo spindle, but I think I need to invest in servos for the x and y axes of my mill.
Re: Advice on buying servos.
Quote:
Originally Posted by
Agathon
Thanks. I notice that you have both DC brushless and AC servos on your website - what are the advantages and disadvantages?
One take DC and the other takes AC, so the AC servo driver has a power supply built in that is rated to the nominal and peak rated current of the driver.
Also Just because it's a DC servo does not mean its brushed, a DC servo can be brushed or brushless.
Re: Advice on buying servos.
Quote:
Originally Posted by
Gary
One take DC and the other takes AC, so the AC servo driver has a power supply built in that is rated to the nominal and peak rated current of the driver.
Also Just because it's a DC servo does not mean its brushed, a DC servo can be brushed or brushless.
OK, that's a very concise reply, but why buy a DC over and AC and vice versa?