Thoughts Please- IM151 Issue

Hi All,

I am building a Profibus network using a Mitsubishi QJ71PB92D Profibus Master Module.

Current Setup: -

1- Profibus Master (Resistor On) 1.5Mbps
11- 32 Words In/Out (Robot)
21- 32 Words In/Out (Robot)
65- 5 Bytes In/ 3 Bytes Out IM151 ET200S (Resistor On)
(P/N: 6ES7-151-1AA05-0AB0 V2.2.2)

Everything was working fine until I added a DP/DP Coupler which is moving 136 Bytes "out" across my network between 2 masters, now it looks like the following

1- Profibus Master (Resistor On)
11- 32 Words In/Out
21- 32 Words In/Out
6- DP/DP Coupler 0/136 Bytes
65- 5 Bytes In/ 3 Bytes Out (Resistor On)

I have no bus faults or errors on any of my network, however the IM151 is no longer transferring any data (so inputs are illuminated, no outputs). I have toggled signals via my CPU with an empty program (just the Profibus Config) and nothing physically works at the hardware end. There are no error lights (both the SF/BF lights are extinguished).

If I delete the DP/DP Coupler from my config, the IM151 starts working again- which points to baud rate or something to do with data transfer. This is the only way I can get it to work.

I have ran profitrace on my network and see Node 65 is constantly trying to sync, I checked over some termination issues also, replaced the IM151 header with a high feature- result is still the same.



Any ideas please?

Please clarify:
When the IM151 starts working again, you are removing the coupler from the configuration, but leaving it powered on and wired to the network, correct?

I think you have a cabling/connection problem...

Make sure you have A to A (green wire) and B to B (red wire), and proper connection on the shield to the casing of all Profibus connectors.

If you're using the insulation displacement Profibus connectors... a common mistake is stripping the end of the wires... do not do this!! Another common mistake is not to insert the wires far enough into the connector.

RVaughan said:

Please clarify:
When the IM151 starts working again, you are removing the coupler from the configuration, but leaving it powered on and wired to the network, correct?

Click to expand...

When I removed the coupler from the configuration entirely (not marking as "inactive") it will start working again.

If I just mark the coupler as "not active" in the configuration, the fault still persists.

sigmadelta said:

I think you have a cabling/connection problem...

Make sure you have A to A (green wire) and B to B (red wire), and proper connection on the shield to the casing of all Profibus connectors.

If you're using the insulation displacement Profibus connectors... a common mistake is stripping the end of the wires... do not do this!! Another common mistake is not to insert the wires far enough into the connector.

Click to expand...

Hi there,

I have rechecked terminations- they are good, I also ran some separate leads which I know are good, still no difference.

I also tried a firmware upgrade of the IM151 last night, no different as expected.

I have uploaded the Profitrace Report

https://file.io/EDTKJCct20rK

Thanks to all for their support.

edit: please ignore Node 64, this was Node 65's original configuration, I copied it to Node 65 so I could make some adjustments to the config and revert back once the problem was located.

Try adding an input area to the DP/DP coupler, even if you won't use it.

sigmadelta said:

I think you have a cabling/connection problem...

Make sure you have A to A (green wire) and B to B (red wire), and proper connection on the shield to the casing of all Profibus connectors.

If you're using the insulation displacement Profibus connectors... a common mistake is stripping the end of the wires... do not do this!! Another common mistake is not to insert the wires far enough into the connector.

Click to expand...

sigmadelta said:

Try adding an input area to the DP/DP coupler, even if you won't use it.

Click to expand...

I just added 8 BYTES out of the coupler on this side (so 8 BYTES input on the other master), all DP errors cleared but still the same issue with the IM151.

Profibus,
Terminations need to be on each end of network. These are the on/off switch on the connector. As people pointing out some profibus connectors are the vampire type, where you just need the red and green wires showning. Is the shield passed thru the connector to rest of network? I know in some profibus networks shield grounding is done on both ends not sure why but could be a problem?
I thought profibus only went up to node 64 at most, same as devicenet, controlnet, etc...
Have you looked the diagnostics information on the scanner module? Should show you what is communicating, issue when its not, the error code when its not communicating.
I thought like all scanner modules there is a run mode versus the not run state/program mode/config mode. Is it in run mode?

Jim3846 said:

Profibus,
Terminations need to be on each end of network. These are the on/off switch on the connector. As people pointing out some profibus connectors are the vampire type, where you just need the red and green wires showning. Is the shield passed thru the connector to rest of network? I know in some profibus networks shield grounding is done on both ends not sure why but could be a problem?
I thought profibus only went up to node 64 at most, same as devicenet, controlnet, etc...
Have you looked the diagnostics information on the scanner module? Should show you what is communicating, issue when its not, the error code when its not communicating.
I thought like all scanner modules there is a run mode versus the not run state/program mode/config mode. Is it in run mode?

Click to expand...

I will do some more continuity checks later regarding shielding, however all shielding is terminated at both ends, the length of the network is only approx 7metres.

Profibus devices can reach 126 (127 and 0 are reserved addresses.

There are no diagnostics apart from that in the profitrace attachment, I have no network faults of diagnostics on the network itself- but the IM151 is not trading IO.

I have proved my program or network calls are not the issue, i tested this my removing all device calls- and manually toggling the output address (which stay toggled), however nothing actually updates at the hardware itself. Program and calls are all now back to normal.

I just checked ohms across network


Green-Green from Node 1 to Node 65- 1.7Ohm
Red-Red from Node 1 to Node 65- 1.7Ohm

A-B at Node 1- 110Ohm
A-B at Node 65- 110Ohm
A-Shield- 7.6MOhms
B-Shield- 7.6MOhms

When I cross a Terminating Resistor on a spare plug- its got 220Ohms across A-B.

So I've managed to get it working- by mapping the profibus config as x1 8 BYTE output and 8x 16BYTE Outputs, now everything is working fine, any ideas?

The .GSD file allows for up to 64BYTE chunks.


Regards

Daniel

The GSD may allow, but your Profibus Master might not allow.

sigmadelta said:

The GSD may allow, but your Profibus Master might not allow.

Click to expand...

Agreed- however it was accepted in the compiler.

Glad it working, however I also tried the original setup in the newer QJ71PB92V and this also did not work.

Thanks for your input.