Motor does not spin

[Sarevok]

Here's the problem. I connected Umi 7764 and a Pacific Scientific P70360 drive, with the following wiring:

umi 7764 screw terminal -> p70360 J4 command i/o 26 pin female connector

inhin1 (bar above) ->  fault- (pin 😎

inhout1 (bar above) -> enable- (pin 6)

step (cw) -> step- (pin 2)

dir (ccw) -> dir- (pin 4)

+5 V (same screw on the same axis) -> enable+, step+, dir+ (pins 1, 3 and 5 respectively)

And, to the required inputs section of the umi I connected to the +5V screw a +5V source I/O power (pin 19).

The drive has the led lit green (meaning system is ok) all the time it's powered on.

At 1D Interactive, I made a velocity test (operation mode - velocity), set the physical parameters (speed, accel, etc.) pressed start, yet the engine does not move. The parameters are: 200 rpm speed, 100 rps/s accel and decel, target position 500 steps. "Current direction si forward" and "axis is moving" are lit green, yet the motor is not spinning.

Did I miss something at the wiring? And how do I tell that the UMI is powered up? It's an UMI 7764, has no leds. Oh, I use a pci 7340 motion controller, connected via a cable with a lot of pins to the UMI.

 http://zone.ni.com/devzone/cda/tut/p/id/3442  , figure 4A, that's the wiring scheme I used.

Thanks in advance.

[Jochen]

Sarevok,

the UMI-drive cabling sounds ok to me, so I think we should focus on the configuration of the P70360 and the motor cabling. If your motor is bought from NI and/or is supported directly by the P70360, you should be able to configure it through the dip switches. With this said I strongly recommend to use the P7000 tools and a serial link from your PC to configure the drive. This method provides methods to test the drive and the motor without using the 7340 and the UMI. This simplifies troubleshooting significantly.

The P7000 tools also provide an option to adjust the drive to the motor's inductance to optimize the drive's performance. With some motors this step is absolutely necessary to make the drive work at all.

If you don't own a serial programming cable, please refer to our online catalog (P/N 780099-01)

I hope this helps,

Jochen Klier

National Instruments

P. S.: If these hints don't help you to get the system up and running, please provide information about the motor type.

Message Edited by Jochen on 05-19-2009 10:48 AM

[Sarevok]

Thank you, Jochen, for your reply.

I forgot to say that I have a T21NRLC stepper motor. And now I have a question. Can I use a serial to usb port to make a serial connection between the drive and the host computer?

[Jochen]

USB-RS232 adapters create a virtual COM-port for Windows which ideally doesn't differ from a real COM-port. So yes, you should be able to use such a device to communicate to the P70360. I have just made the experience, that some very cheap adapters don't support all the features of a legacy RS232 interface, so there is a small chance of trouble with such a configuration. If you are looking for a high quality adapter, this link might be interesting for you, but it's definitely not mandatory to use an NI device for this purpose.

Jochen

[Sarevok]

Hi, Jochen

Unfortunately, P7000 tools does not detect the drive, even when connected to the serial port and powered on. Now, the serial cable is "improvised": first, on J5 i connected something that has a tag that reads "USB AF - RJ11". The RJ11 side fits the J5, and it has 6 grooves, the 2 in the middle (groove 3 and 4) has wires, the rest is NC. The other side of the connector is USB. From the computer first it's connected a female to female 9-pin d-sub adapter to the 9-pin d-sub male to usb. In short:

Host computer (9 pin d-sub male) -> 9 pin d-sub female to female adapter -> 9 pin d-sub male to usb cable -> USB AF - RJ 11 adapter -> J5 connector.

I made this improvisation since I couldn't find the direct serial cable (i mean 9-pin d-sub female to RJ-11), and buying online is very expensive.

Thanks in advance

[Jochen]

Sarevok,

do you really expect this stack of adapters to work? The first mismatch in this chain is a the 9 pin d-sub male to usb cable. This means you try to convert a standard RS232 port into a USB port and then you try to convert it back to RS232. That's definitely not possible. In addition the pinout of your RJ11 cable is probably wrong.

If you don't want to buy the cable, you can crimp and solder it by yourself. You can find the pinout in the P70360 user manual in chapter 2.2.3, but unless your hourly rate is really low, ordering the cable is probably the cheaper option for your company.

Kind regards,

Jochen

[Sarevok · Accepted solution]

Hi Jochen,

I managed to solve the spinning problem. What I were 2 wires which go to the required inputs terminals. I wired them and now, via MAX and a few example c programs the motor is spinning, in other words is working, in open loop mode.

Thank you for answering.