How to connect a Danaher motion's S20360-VTS drive to NI's UMI7764

[Sasidhar]

Hi all,

I am looking to connect Danaher motion's S20360-VTS drive with NI's UMI-7764 and eventually to PXI-7352. The S20360-VTS is intended to drive the gearmotor under torque control (+/- 7.5 Nm with a safety factor of 2 so +/- 10 Nm). I am having a confusion with the wiring in between the drive and UMI-7764. Can anyone please guide me with this? Anysort of help would be really appreciated.

Thanks,

Sasidhar. 

[Jochen]

Sasidhar,

could you please provide the datasheet of the drive? This would help us a lot to answer your question. Please provide also information about the motor and the feedback device.

Thanks and kind regards,

Jochen Klier

National Instruments

[Sasidhar]

Hi Jochen,

Thanks for the prompt reply. Here is the information about the drive and the motor.

For Drive: Model no. 20360-VTS Base drive

                 Wiring dwg. Ref. pg 30 in datasheet.

For Motor: Model no. AKM22E-VBPNC-00

                  It is a AKM series brushless gearmotor with Precision Line gearhead, 60 mm frame, 10:1 reduction ratio, 0.5 meter

                  shielded cables w/ single Molex plug, w/o brake, smart feedback device. 

Thank you.

Sasidhar. 

[Jochen]

Sasidhar,

thank you for the datasheet. To me wiring seems to be quite straight forward. The drive provides inputs (J4: 24,25) for the analog output signals of the 7352 and it can generate an emulated encoder signal (J4: 17 - 22). Do you have any specific problem with the wiring?

Thanks,

Jochen

[Sasidhar]

Hey Jochen,

            How are you doing? I apologize for replying so late, had been working in the machine shop lately for the same project. So, back to the control part; you mentioned that "drive provides inputs (J4: 24,25) for the analog output signals of the 7352". So please guide me if I understand this correctly; all of the wiring we need is,

  1) +5V power supply going to pin 11 and gnd to pins 5 and 12 of UMI-7764.

  2)  A twisted pair cable connecting the drives inputs (J4: 24,25) to UMI's pins 6 (analog o/p) and 7 (analog o/p gnd) respectively.

And just plugging in UMI-7764 to PXI-7352 via SH68-C68-S. Also I am new to LabVIEW in all, so how to read the UMI-7764 in LabVIEW; I mean do we have to create a VI for that or motion assistant application can do it easily. We are in the process of getting a full version of LabVIEW licensed to the University to our dept. So, for the timebeing it is the version that came along with PXI-8108. Also, several CD's came along with the NI shipment, do we have to load all of them into 8108 or they are already loaded.

            And what about the reading back from the motor to control it when it reaches desired torque? We are using a TRT-100 torque cell. What I saw from the forums is that TRT-100 needs to be connected to SCC-68 which in turn to PXI-6251 M-DAQ. How are the connections in between TRT-100 and SCC-68? The specs for TRT 100 are,

Rated Output (R.O.): 2 mV/V nominal
Nonlinearity: 0.1% of R.O.
Hysteresis: 0.1% of R.O.
Nonrepeatability: 0.05% of R.O.
Zero Balance: 1.0% of R.O.
Compensated Temp. Range: 60° to 160°F
Safe Temp. Range: -65° to 200°F
Temp. Effect on Output: 0.005% of Load/°F
Temp. Effect on Zero: 0.005% of R.O./°F
Terminal Resistance: 350 ohms nominal
Excitation Voltage: 10 VDC
Safe Overload: 150% of R.O.

           I know I am being too exacting in this issue, but I come from an all together different background in my undergrad and the electrical and control part is very new, so just do not want to mess up things. So learning one thing at a time as we progress, but again time is a contraint so cannot afford to be too slow also. Absolutely any sort of help would be greatly appreciated. Heartfelt thanks once again to NI team.

Regards,

Sasi.

[Jochen]

Sasidhar,

I have added some answers to your post in blue.

Hey Jochen,

            How are you doing? I apologize for replying so late, had been working in the machine shop lately for the same project. So, back to the control part; you mentioned that "drive provides inputs (J4: 24,25) for the analog output signals of the 7352". So please guide me if I understand this correctly; all of the wiring we need is,

  1) +5V power supply going to pin 11 and gnd to pins 5 and 12 of UMI-7764.

No. As you can see in the UMI-7764 manual, you need to provide +5V to the power terminal at the lower part of the UMI's PCB. The connector that you mention outputs +5V from this  power connector for sourcing further external equipment

  2)  A twisted pair cable connecting the drives inputs (J4: 24,25) to UMI's pins 6 (analog o/p) and 7 (analog o/p gnd) respectively.

Correct.

And just plugging in UMI-7764 to PXI-7352 via SH68-C68-S. Also I am new to LabVIEW in all, so how to read the UMI-7764 in LabVIEW; I mean do we have to create a VI for that or motion assistant application can do it easily. We are in the process of getting a full version of LabVIEW licensed to the University to our dept. So, for the timebeing it is the version that came along with PXI-8108. Also, several CD's came along with the NI shipment, do we have to load all of them into 8108 or they are already loaded.

Motion Assistant is good for simple positioning tasks. As you want to do torque control,  Motion Assistant is not a good choice. Better use LabVIEW for the programming. You need to install LabVIEW and NI-Motion, which provides the API functions for the 7350.

            And what about the reading back from the motor to control it when it reaches desired torque? We are using a TRT-100 torque cell. What I saw from the forums is that TRT-100 needs to be connected to SCC-68 which in turn to PXI-6251 M-DAQ. How are the connections in between TRT-100 and SCC-68? The specs for TRT 100 are,

For torque control with direct feedback from a torque cell you need to connect the output signal of the torque cell to an analog input of the 7350. Please click here for more information about using analog feedback with NI-Motion control devices. You can't use a DAQ device (PXI-6251) for this purpose, as you couldn't use the readings from the DAQ device as a feedback signal for the control loop on the 7350. Still you will have to use an external amplifier for your torque signal to align it with the input range of the 7350's analog inputs (0 - 5 V, +/- 5 V, 0-10 V, +/- 10 V selectable). The maximum output value of your torque cell seems to be 20 mV, so you should at least apply a gain of 100 to your torque signal. Unfortunately you can't use a SCC-68 for this purpose, as it doesn't provide connectivity to the 7350, so you will have to use an amplifier from another vendor.

Rated Output (R.O.): 2 mV/V nominal
Nonlinearity: 0.1% of R.O.
Hysteresis: 0.1% of R.O.
Nonrepeatability: 0.05% of R.O.
Zero Balance: 1.0% of R.O.
Compensated Temp. Range: 60° to 160°F
Safe Temp. Range: -65° to 200°F
Temp. Effect on Output: 0.005% of Load/°F
Temp. Effect on Zero: 0.005% of R.O./°F
Terminal Resistance: 350 ohms nominal
Excitation Voltage: 10 VDC
Safe Overload: 150% of R.O.

           I know I am being too exacting in this issue, but I come from an all together different background in my undergrad and the electrical and control part is very new, so just do not want to mess up things. So learning one thing at a time as we progress, but again time is a contraint so cannot afford to be too slow also. Absolutely any sort of help would be greatly appreciated. Heartfelt thanks once again to NI team.

Regards,

Sasi.

[Sasidhar]

Thanks Jochen, I shall start with that you have provided and in case get stuck again, will come back to you.

Sasi. 

[Sasidhar]

Hey Jochen,

I connected +5 V and gnd to the power terminal at the lower part of the UMI's PCB. Power supply is also given to the pins +5 V and digital gnd connections mentioned on axis 1 part on the board. A twisted pair cable runs from AOUT1, AOGND, and digital gnd to the pins J4: 24,25, 26 on S20360 drive respecticvely. When I connect to LabVIEW MAX and goto NI Motion controller and in that default 7350 settings to see atleast whether the motor is being seen by the system, there is an error status open stating that "You need to run clean powerup status command or VI for the controller to funtion". 

Can you throw some light on this issue? Though I still have some doubts like,

1) We are just connecting drives Analog input +, Analog input -, and Input return pins to Analog out 1, Analog out gnd, and Digital gnd pins of UMI7764. And ofcourse the drive powers the motor and reads its SFD via J3 and J4 slots respectively. (S20360 datasheet attached for ref.). So, how is the exact communication happening in between the motor and LabVIEW? And for control purposes after reading from the torque cell, how does LabVIEW tell the motor to stop and do what has been programmed?

Thanks.

Sasidhar. 

[Eric_R]

Hi Sasidhar

I believe we spoke on the phone earlier today regarding your motion control system and the motor not responding. For questions regarding how to program our motion controller cards and their interaction with LabVIEW please reference the NI-Motion Concepts Manual. In chapter 13 specifically the subject of torque control is reviewed in detail and the recommended control loops are shown. Also please note that LabVIEW and MAX will not "see" the motor in the same sense that your computer may detect a USB device. Measurement and Automation Explorer will take the settings you input based on the drive you are interfacing with and use this to control how it communicates with it. Only feed back is what the controller detects from the drive, so you may get a following error if the motor is disconnected.

[Sasidhar]

Hi Eric,

Thanks a lot for your inputs. After speaking with you I went over everything once again with a cool mind and got it working. Where the problem lied is that, I misunderstood gnd connections and failed to connect the DINPCOM (Common sink to Enable, Inhibit+/-, Dir pins) pin connection on the S20360 drive. It basically kept the circuit open. Thanks once again for your help. Since, this is solved just gotta start learning LabVIEW programing and come up with a control algo. And in case I come across any difficulties along way I shall come back to you. Thank you.

Regards,

Sasi.