1336 VFD on ControlNet SLC500

[noob]

Hi,
I have 4 VFDs ( Allen Bradley 1336 plus II) on ControlNet, controlled by PLC SLC500, L542 processor. All this is a part of the building automation system. The problem is when VFD #3 is run in AUTO mode, it runs for about 30 mins and then stops without any alarm on the HMI. Only the building automation system generates an alarm saying VFD 3 failed to start.
An encoder is used. Just wondering what is stopping the drive? Is it a bad cable connector or something else? The drive runs fine is Manual mode. Any help would be highly appreciated.
Thanks.

 

[AlfredoQuintero]

I am not an expert in motion so my advice may not help. Anyways, here it goes: one thing which is very nice about CIP protocols such as ControlNet, DeviceNet and EtherNet/IP is that the indicator specification is common and very thoroughly specified. So if you can provide a description of the behaviuour of the MOD/NET status LEDs I could provide you a hint on whether the problem is related to communication or related to application or module itself. For example if there is some grounding problem which does not manifest itself when the driver is idle, but which at some particular state of the drive makes the communication impossible, you would see abnormal NET LED behaviour, whereas if the problem is more of the application kind, the MOD status would provide some hints.

 

[noob]

Thanks.
Three indicators on controlnet 1203 module are lit solid green. Channel b is not used so it's led is off.
Channel A, scanport and controlnet are solid green. And I compared with others, it's the same.
Thanks once again.

 

[AlfredoQuintero]

So, then I think you do have an application problem, not a communication problem. I am sorry I am unable to provide additional information. What is the product type of this device? if it is a product type defined by the CIP specification, I can have a look at the spec and provide further advice if you give me more information. But there are other members of this forum who are so knowledgeable of Rockwell drives that I think it will be better to wait until one of them takes a look at your post, unless you really need to have some information like right now.

 

[noob]

Thanks Alfredo. By product type you mean VFD used for? or some sort of a serial number? Sorry didn't understand that.

 

[AlfredoQuintero]

Sorry, I meant Device Type Number, which is instance attribute 2 of the Identity Object. The CIP specification has a number of device profiles defined, and if the device conforms to a particular profile, we can use the profile specification. However, if the profile is a vendor specific profile, then we have to refer to the specification from the vendor.
Below is an extract of the CIP spec.

 

[noob]

Thanks Alfredo. By product type you mean VFD used for? or some sort of a serial number? Sorry didn't understand that.

 

[noob]

Sorry Alfred, where would I find that info? contronet module, scanport splitter, vfd or plc which part? Sorry I have no clue about this.

 

[AlfredoQuintero]

Do you have the EDS file of the device? The EDS file would describe all attributes in the identity object.

 

[AlfredoQuintero]

I mean the EDS file for the VFD

 

[noob]

Thanks Alfredo. This electronic data sheet is available in .dno file or I have to connect RSLinx to retrieve that. I have the .dno file.

 

[AlfredoQuintero]

usually the EDS file is available from the vendor's website. It should be.

 

[noob]

Thanks Alfredo. I will check that.

 

[Ken Roach]

A blast from my past

then stops without any alarm on the HMI.

Do you mean that you are examining the LCD "Human Interface Module" on the 1336 Plus II drive itself ?

Typically, of course, when a drive loses comms with the PLC it will generate a fault code on the display.

So yours is either stopping because it's been told to, or because it's been configured to stop and not fault, or because it's being automatically reset.

Do you have a 1203-CN1 external ControlNet to SCANPort module on the drive ?

Those devices can be set up to react differently to a ControlNet connection loss than to the PLC going into PROG mode.

The default is to cause a fault on the drive, just like if you had unplugged the SCANPort cable. But they can also be set up to go to "Comms Fault Action" and simply stop the drive without causing a SCANPort fault. I once programmed an application where the 1336 Plus II would react to a network fault by turning on in reverse direction and 10% speed until it hit a hardwired limit switch !

Your system isn't easy for a novice to use: you have a 1747-SCN15 scanner in the SLC-500 chassis, which has its scanlist and ControlNet schedule set up with RSNetworx for ControlNet software. You might also have a serial/ControlNet module (1747-KFC15, I think) or another ControlNet interface (1784-PCC card, or 1784-U2CN).

How often does the SLC-500 program command starts and stops on these drives ? Is the 30 minute runtime precisely 30 minutes, or does it vary ? How often does the "failed to start" alarm occur ?

The 1336 Plus II has a simple "fault queue" that will show you the last four faults that occurred on the drive. It's described in Chapter 3 of the user manual.

https://literature.rockwellautomation.com/idc/groups/literature/documents/um/1336f-um002_-en-p.pdf

A serial fault (F 10) means a disconnection of the SCANPort cable between the drive main control board and the ControlNet interface module. If my memory is correct, Fault 10 also happens if the 1203-CN1 is configured to fault the drive when the ControlNet connection fails or goes to PROG/IDLE mode.

 

[noob]

Thanks Ken.

Do you mean that you are examining the LCD "Human Interface Module" on the 1336 Plus II drive itself ?
Yes, I meant HIM

Typically, of course, when a drive loses comms with the PLC it will generate a fault code on the display.
No Fault code is generated

So yours is either stopping because it's been told to, or because it's been configured to stop and not fault, or because it's being automatically reset.
I believe it has been programmed that way.

Do you have a 1203-CN1 external ControlNet to SCANPort module on the drive ?
Yes, there is a 1203-CN1 module and a scanport splitter installed.

Those devices can be set up to react differently to a ControlNet connection loss than to the PLC going into PROG mode.

The default is to cause a fault on the drive, just like if you had unplugged the SCANPort cable. But they can also be set up to go to "Comms Fault Action" and simply stop the drive without causing a SCANPort fault. I once programmed an application where the 1336 Plus II would react to a network fault by turning on in reverse direction and 10% speed until it hit a hardwired limit switch !
In my case, it just says Stopped on the HIM.

Your system isn't easy for a novice to use: you have a 1747-SCN15 scanner in the SLC-500 chassis, which has its scanlist and ControlNet schedule set up with RSNetworx for ControlNet software. You might also have a serial/ControlNet module (1747-KFC15, I think) or another ControlNet interface (1784-PCC card, or 1784-U2CN).
Yes, it’s a bit involved.

How often does the SLC-500 program command starts and stops on these drives ? Is the 30 minute runtime precisely 30 minutes, or does it vary ? How often does the "failed to start" alarm occur ?
Its roughly 30 minutes. It always happen when run in AUTO mode.

The 1336 Plus II has a simple "fault queue" that will show you the last four faults that occurred on the drive. It's described in Chapter 3 of the user manual.
I will find out that parameter. But last fault when checked was not listed. It stops and doesn’t log it as a fault. So probably won’t be in the list of faults.

https://literature.rockwellautomatio...m002_-en-p.pdf

A serial fault (F 10) means a disconnection of the SCANPort cable between the drive main control board and the ControlNet interface module. If my memory is correct, Fault 10 also happens if the 1203-CN1 is configured to fault the drive when the ControlNet connection fails or goes to PROG/IDLE mode.

There is no F10 or any other fault. It just stops on its own after running for 30 minutes or so.