SLC to PowerFlex40 via DeviceNet

[matsusi]

I have a system that uses a SLC5/05 with an SDN card communicating to 13 PowerFlex40 drives using DeviceNet communication. 11 of the drives are on one conveyor system and the other 2 are on another conveyor system. When the one conveyor is not being used I have the bunch of contactors that shut off the corresponding drives. The system works great unless I leave the one conveyor system shut off for an extended period of time (say a full day or a weekend)
When I go to restart the one conveyor the contactors pull in powering the drives. The DeviceNet cards do their usual bootup sequence but are unable to establish communication with the SDN card.
The issue seems to be more associated with the 2 drives and not the 11 drives. I've gone through all parameters with the drives and with the DeviceNet. I do not see anything that is different.
Anyone have any ideas on how I can correct this?

 

[controlsdude]

any device address have a fault on the front of the sdn card?
1747-SDNum652b-en-p.pdf check this pdf out from AB chapter 7 on troubleshooting.

do you wait for some length of time before giving the commandrun signal to the devicenet card for these two vfds?
checked terminations are correct? loose connections?

reseat the devicenet cards in the drives?

Do you have a noise problem on this cable run with the two drives?

You can get a devicenet checker(not sure on the exact part number, looks like a multimeter but for devicenet) from your local rep for troubleshooting your hardware, give them a call and see if they will let you use it.

Answer the questions

 

[matsusi]

Thanks for the quick response controlsdude,
The fault message that I'm getting is 12-78 and 13-78 which is what I'd expect to see when the drives are powered down. On the drive adapters themselves I have a solid green PORT led, a flashing green MOD and NET A led which I'd expect to see if the SDN card was not active.
The 13 drives are all daisy chained in the same panel. I have drive 1 at one end of my chain and the SLC at the other end.
I thought about noise and have scoped the signals and all look clean. I'm using a separate power supply and all comm. cables are routed clear from any power wiring. I checked all of my shielding and it all looks good. I'm thinking that noise is not the problem since I only have 12" of cable between each drive and 3' from drive 13 to the SLC.
I wait roughly 30 seconds from the time I power up the drives until I give the start command. I increased that timer and still no luck.
I have tried reseating the DeviceNet cards but the PORT led goes solid green right away so I'm assuming that the adapter is communicating properly with the drive.
The reason I'm scratching my head over this one is because it seems to be only an issue with 2 of the 13 drives.
If I power down the SLC and then try to restart the whole system I never have an issue.

 

[controlsdude]

check if your procedure follows something like this below
procedure for startup
enable the card after 10 sec, then set Ox/0 bit for that sdn card
send the setup for M0 between the above and below time and copy out M1 parameters.
after you enable the card wait 2 sec then reset the sdn Ox/7 if you have a comm fault Ix/10.

Do you believe the M0 settings are correct that you send to the sdn card?

Do you get back the correct settings from the card for M1?

 

[matsusi]

Well, I'm not using explicit messaging to communicate to the drives. Presently I'm turning on bit O:1/0 after the SLC powers up. Then I see that I:1/0 turns on confirming that the SDN is enabled. I then power up the drives. After a set amount of time I send out a clear fault command to the drives that I have powered up. If I receive back the active, ready and no fault bits from the drive, I then send the run command.

 

[controlsdude]

"Presently I'm turning on bit O:1/0 after the SLC powers up."

Are you waiting some length of time before you turn on O:1/0? Maybe this is the problem, wait like 10 seconds after power up or first scan to enable this bit.

If you get a comm fault (I:1/10) you need to reset it by O:1/7. This could be a problem, presently you not doing this on power up. Maybe you have the comm fault sometimes come up set and you need to clear this by O:1/7?

This first word bits is for the SDN card and you need to take care of the above comm fault status. And also delay the run command bit O:1/0!

 

[matsusi]

Presently I have it O:1/0 to turn on 10 seconds after the SLC is powered up. I'll have to do some investigating and see if I'm getting a comm. fault and maybe I'm just not reseting it when it happens.
Thanks for the help controlsdude!