Power Flex 70 Fault Code 75

Hello guys,

I get Port 5 Adaptor FLT#75 many times on PowerFlex 70 VFD. After reset VFD, it goes away. But happen once in 2 week.

My VFD is connected to 1771 - SDN module via DeviceNet

I am new graduate and not much experience in DeviceNet....

Need Solution.....

Thanks a lot guys...

Powerflex 70 fault code 75

Hello OkeiPC,

How do I find out FRN on RAJ 20-COMM-D card on the VFD ??


And what is 20 - COMM - D?

Thank you

Find out the FRN of your 20-COMM-D module and the FRN of the VFD. You should be able to see this on the hardware labels (unless they have been changed with ControlFlash) but you can also view this information on the HIM or from RSNetworx for DeviceNET. Be aware that the HIM will allow you to look at VFD parameters, and you can also back all the way out of the menus and choose to look at parameters from the COMM module itself by choosing it instead of the drive from one of the primary menus.

Before we start troubleshooting the network or your other hardware, I think it is important to rule out some known issues that existed in certain firmware versions (been there, done that)...

I am working strictly from memory, so the exact parameter numbers you need to view can be found in the User Manuals, or someone else with easy access to them may do the research for you.

Paul

The 20-COMM-D is the module that connects the VFD DPI port to the DeviceNET network.

Give us some background on the system.

It's probably not a new system, since it's using a very old 1771-SDN scanner module and slightly older PowerFlex 70 series drives.

Has it been experiencing these faults for a long time ?

When the faults occur, how do you get the drives back online with the controller ?

Is the problem occuring with just one drive, or several ?

What other devices are on the DeviceNet network ? Are any of them experiencing communication problems ?

Have you done the basic troubleshooting for DeviceNet ? This includes verifying that there is a dedicated network power supply that only runs the DeviceNet network, and that two terminating resistors are in place at the physical ends of the network trunk. With the network and all devices powered down, you should measure about 60 ohms between the blue and white wires.

Powerflex 70 fault code 75

Thank You OkiePC and Ken,

Please see attached Picture of 20-COMM-D. FRN for this is V2.001

I asked Electricians guys, When this fault occurs, They Clear Fault on VFD and Turn Off and ON power on DeviceNet through breaker. And this Fault goes away.

This system is OLD system

We have only this drive is connected with 1771 SDN on DeviceNet. We have same PowerFlex 70 on DeviceNet but that's spare. We are not using spare unit now.

This Fault occurs once in two week and happening since long time.

I already checked it and DeviceNet had independent +24VDC power supply.

Do you think that this can give me problem because DeviceNet cable from 1771 SDN to VFD is running in same panduit, where 480 AC V cables are running.

Thank you very much guys.....

Please bare with my very simple question because I just finished my school and started to work in PLC field.

Do you think that this can give me problem because DeviceNet cable from 1771 SDN to VFD is running in same panduit, where 480 AC V cables are running.

Click to expand...

This is bad practice and should be the first thing you investigate.

DeviceNet is very noise-immune, but no digital network should be run in parallel with high-power AC circuits.

Check carefully for the termination resistors I mentioned. There should be one 120 ohm resistor across the blue and white wires at each end of the network "trunk" cable.

If only the PowerFlex 70 and the 1771-SDN are on the network, then the resistors should be located at those devices.

Powerflex 70 fault code 75

Thank you very much Ken.....

Currently....System is running so i can't check now but tomorrow morning , I will check and post the value of Resister.

I should change panduit and VFD location than.....??

I have attached picture of VFD environment here.....Where you can see that DeviceNet and 480 VAC are running in same panduit ...(Under VFD)

Thank you guys....

A few inches of proximity isn't as bad as when the cables are run in the same conduit for many meters.

If you can route the DeviceNet cables away from 480V cables (it looks like there are quite a lot of them, other than the drive input and output) it might help.

It looks like the second drive might be connected to the network as well; the terminating resistor might be there.

You do have to power down the devices and the DeviceNet so that nothing is trying to put out voltage onto the data pins when you measure the resistance to verify the correct termination.

Also be sure that if the DeviceNet cable has a shield that the shield is grounded at only one location. It should be grounded close to the DeviceNet power supply, and not necessarily at the PLC end of the cable.

Next time there's a fault, have the electricians go inspect the 1771-SDN as well, to see if it's showing a fault code 91 (Bus Off, meaning a major noise or wiring problem) or if it's just showing fault code 72 or 78 (meaning it can't talk to the PowerFlex drive).

Powerflex 70 fault code 75

Thank you Ken....

I will check tomorrow morning and post value of resistance after shutting down power, Value of terminating resistor at both end, One side ground on shielded cable.....

120 Ohm Resistor ( What size in Watts do i need ) ???

We will move this VFDs in July when we shut down.....

One Electrician ask me this question....." When he tries to change Parameter in VFD, he can make change but it doesn't apply...It goes back to it's original parameter. When he shuts down power from Dnet, he can change it and change applies but when he put Dnet power On...this parameter goes back to it's original setting"

Please Advice....

The terminating resistors are very small; I always use 1/4 Watt.

What is very likely happening with the parameter change your electrician is describing is that a "Data Link" configuration is over-writing that parameter.

By default, the 1771-SDN sends just two 16-bit Words of data to the PowerFlex 70; Command and Reference. It receives just two 16-bit Words of data; Status and Feedback.

But the 1771-SDN and the 20-COMM-D can be configured to send and receive larger blocks of data that are linked to other drive parameters. The 20-COMM-D will apply the data values it receives over DeviceNet to those parameters in the drive.

These are called "Data Links".

DataLinks are complex enough that it's hard to explain in a single Forum post how they work. They are well described in the User Manuals and in dozens of Knowledgebase documents and examples.

If you can upload the RSNetworx for DeviceNet configuration file that includes the 1771-SDN Scanlist and the PowerFlex 70 configuration and post it here (ZIP it first), Forum members may be able to explain exactly which parameters are set up as DataLinks.

Please see attached DNT file

Thank you very much