|
Register | Options | Profile | Last 1 | 3 | 7 Days | Search | Today's Posts | Mark Forums Read |
|
Thread Tools |
#61
|
|||
|
|||
Quote:
Mike, I have a problem with your "bipolar half-coil" wording because I have always called that "unipolar (half-coil)". The reason I choose to insert the term "unipolar" is because of Oriental Motor's spec sheet which gives two sets of ratings for 6-wire motors "bipolar(series)" and "unipolar". For our half-coil connections, we use the inductance & current ratings in the "unipolar" section of the OM data sheet. |
#62
|
|||
|
|||
Gerald, you are correct in stating that we have all used the term Unipolar (half-coil). You and I know what it means, but I receive dozens of emails every week asking me how I use a Unipolar motor with a Gecko.
I'm afraid that the term "Unipolar" is causing a lot of problems when motors are used with Gecko stepper drivers. The term "Unipolar" has two meaning when used with a stepper motor. Unipolar describes the electrical characteristics of the motor, (Voltage, Current, Inductance, etc.) but it also describes how the power transistors are used when driving the motor. The term "Bipolar" also describes how the power transistors are used in the stepper driver. All Gecko stepper drives are Bipolar drives. Half-coil describes a method of connecting the motor to the stepper driver using only four wires instead of the six wires required by a true Unipolar connection. It can all be very confusing because we use the Unipolar electrical data to size the power supply and current limiting resistors, but we use a Bipolar physical connection when we connect the motor to the driver. Probably the most proper way to tell someone how to connect a motor and size a power supply would be to tell them to use the Unipolar motor data, but to realize that they are going to use a Bipolar stepper driver; therefore, they only use four wires when connecting the motor to the driver. |
#63
|
|||
|
|||
Mike, I realised today that "bipolar half-coil" has been mentioned before:
(From Oriental Motor reference) |
#64
|
|||
|
|||
Quote:
If your going to use a reduction like I am, then power probably won't be an issue. If you won't be needing a 4th axis ( indexer ) then the the G-540 will most likely work. My g-540 arrived today, it is actually larger than I thought it would be. My power supply is on its way as are the motors. Dave |
#65
|
|||
|
|||
Gerald,
And here I thought that I had coined a new term. Oh well, maybe next time. |
#66
|
|||
|
|||
HELP !!!!! This is too much! I have tried to understand this a long time now.
My technical english is not good! Is this right? Trying to find out how much power supply I need. 5 motors. Rated current 4 A. Phase Inductance 5,50 mH 4A x 5 Motors x 0,67 = 13,40 A 5,5mH= 2,3452079 x 32 x 0,75 = 56,28 V Power supply= 13,4 x 56,28 = 754 Watt ( is this right?? ) I connect directly from power supply to the driver, and on to the motor? Do I need some components between some places? Do anyone have a map with all componentes connected? I thinking buy power supply from USA, and I don noe what I need. I must have a transformer, from 220-230 to 40-60, which is the drivers should have input. Is it some transformers I can tuning between 40-60? Thanks! |
#67
|
|||
|
|||
4A X 5 motors = 20A total. Depending on how hard you use the motors, 13A to 20A would be required. (Unless I'm certain that I would be under-running the motors, I would use a 20A power supply.)
32 X SQRT(5.5 mH) = 75VDC MAXIMUM. 56V to 75V will work. The higher the voltage, the hotter the motor. You have the correct formula for wattage, i.e. Volts X Current. So, depending on the Amps that you expect and the Voltage that you select, a power supply capable of handling 750W to 1,500W will be necessary. A 40VAC transformer would give you about 56VDC. 20A X 40V = 800VA, so you will need a transformer rated around 750VA. You will need about 20,000 to 30,000 uF capacitance, again depending on how hard you drive those motors. The working voltage of the capacitors should be the power supply's voltage X 125% to 150%. There are other minor considerations depending on the hertz (50 or 60) and the efficiency of the components, but power supplies for stepper motors do not have to be exact. Stepper motors will run very well with a power supply putting out 100% of the expected voltage and they will still run very well with a power supply putting out 75% of the expected voltage. A CNC router does not normally stress its motors. Most of the time one or more of the motors will be very lightly used. You will need to carefully study the Gecko stepper driver data sheet. The power supply is connected to pins 1 (Ground) and 2 (Power). The motor is connected to the A, the /A, the B and the /B terminals. DO NOT connect the power supply directly to the motors. The Gecko provides the power to the motors. www.antekinc.com offers several power supplies that fit your specifications. They have the PS-8N54 (54V @ 800W), the PS-8N63 (63V @ 800W), both voltages in the PS-10Nxx series (1,000W) and both voltages in the PS-15Nxx series (1,500W). |
#68
|
|||
|
|||
Thanks!
It was good information. Now, I have learned a little more. |
#69
|
|||
|
|||
Svein & Mike
There is some confusion here. Svein is going to use the MotionKing drive that accepts AC power input direct direct from a transformer. Mike's advice is based on Geckodrives. Svein's drive data is in this post: http://www.mechmate.com/forums/showt...&postcount=108 Svein, you do not need to purchase a "power supply". You only need a transformer between 40 and 60 volts. A 50 volt transformer would be quite common. The document of Motionking says your transformer current must match the drive current. We don't know how much heat the Motionking drives make, so we cannot guess that a smaller transformer will be okay. Gecko gives the factor 0.67 - for MK the factor must be assumed as 1.0 until we have better information (measurements). Therefore, for 5 drives switched on at the same time, connected to 4 Amp motors, MK says to use a 20 Amp transformer. |
#70
|
|||
|
|||
See part number 223-8421 from http://no.rs-online.com/web/ as an example. That transformer has two output coils 50V at 10 Amp each, you will put them in parallel to give 50V 20 Amp.
|
#71
|
|||
|
|||
Great! Thanks
It is easy to become confused in here.. That transformer looks good. Now I understand much more. I think I will try 50V input on drivers. Have heard a lot about rs-online, they have probably the rest of elekto parts I need. Thanks Gerald. |
#72
|
|||
|
|||
The transformer at RS-Online is made by Nuvotem of Ireland, who sell direct to Norway. See http://www.nuvotem.com/en/contacts/norway.shtml
You can ask them for part no. 1000P1-2-050. Datasheet |
#73
|
|||
|
|||
Thanks!
I also need a transnational forms of PDMX. RS has certainly 9V Transformer to PDMX also. I can connect the AC 50V directly to drivers, but where should I connect 9V transformer? After that I have 50V and 9V transformer, drivers, PDMX and motors. I do not need any more componentes to run the machine? E-stop and limit switch i must have. Sorry for all the questions! |
#74
|
|||
|
|||
Transformer to PDMX. Should I write. (on the first line in the last post)
Sorry my bad english! |
#75
|
|||
|
|||
Need Help Wiring ANTEC PS and G540
Quote:
Thanks Joe |
#76
|
|||
|
|||
Joe
The G-540 is very simple to wire, The instructions are very good. I was overwhelmed at first, but the more I read the clearer it became. I don't have e-stops wired up yet, so there only three wires I have connected to the G-540, all three to the power supply. I have connection #11 on the gecko to the positive side of my power supply output. I have connections #10 and #12 to the negative side of the output of my power supply. Those are the only wires I have connected to the input side of my G-540. I need to hook up the e-stops on my machine and I will before I have the remote xbox controller working. As far as the power supply is concerned, have a look at the kitchen table project, That's pretty much what we all used for our wiring set up. One important thing to do is be sure to FUSE THE POWER IN TO THE POWER SUPPLY. Don't ask me how I know, but I will tell you that it cost about $100. Antec has the instructions how to wire the power supply on their web site on the spec sheet. Dave |
#77
|
|||
|
|||
Dave: Thanks. Unfortunately, my power supply is the only one (apparently) where the PDF spec sheet doesn't work! However, Mike showed me that the other spec sheets work and I am using one of those. Do you recommend the optional fuse module for the ANTEK PS? If so, I will order one. Does it have to be installed by ANTEK or can I do it?
Joe |
#78
|
|||
|
|||
Just spoke to John at ANTEK who is sending the fuse module. Self-install is OK. Joe
|
Register | Options | Profile | Last 1 | 3 | 7 Days | Search | Today's Posts | Mark Forums Read |
Thread Tools | |
|
|