ModBus and Altivar Invertors

[denise01 3]

Hello Lost Control, made an attempt at the Altivar 31 today. Cant seem to connect the Altivar on serial link, is there any way of knowing I keep getting a flashing alarm SLF which would signify no connection. Am using the Baud rate and 19200 and 8,1 Even bits as recommended. Have set LAC to L3 but will keep trying. Where does 0C81 come from in the Read and also 2135 in the write is that the HEX value of the address. Anyway many thanks Lost Control will work through it all. Regards Peter

[lostcontrol 23]

I mentioned contiguous. To me, this means that the registers you are wanting to read are one after the other; 3201, 3202, 3203 etc. Perhaps consecutive would of been a better term. In the ATV31, they are consecutive. What this means is that it may be more efficient to create a custom Protocol Macro for the ATV31's. This would reduce the PLC code required for the Easy Modbus & free up some memory. To begin with though, lets see if you can get the Easy modbus functioning to a single inverter first. Another thing to check, are you using a single PLC for this, or something that is doing other tasks? Reason is that you need to be very careful that your other tasks do not use the same IO that the Easy Modbus does. if this happens, things will not work as expected! ATV31-CP1LCP1HCJ1CJ2CS1ModbusSolutionV211good010912.cxp

[denise01 3]

Hello Lost Control, Bit of a fruitless day trying to connect to the Altivar downloaded Serial Connection Manual from Omron and discovered that the connections from the RJ45 should go to pins 1&2 on the com port 1 SCU31. will reconnect tomorrow. Was looking at the Altivar 31 Modbus manual and it said that the digital codes for Modbus were 3, 6, 16 and 48. I wondered if these were the functions that you used in the sample programme. Good news I am learning all the time, quite frustrating lots of things have to be in place. Regards

[BobB 58]

Be careful - pin 1 is negative and pin 2 is positive in the 9 pin plug.

[denise01 3]

Yeah thanks Bob I am quite confident all connections and settings are okay. I noticed in the Altivar Modbus Manual that the Altivars supported Functions are READ Function 3 and for Write Function 6. Does that mean that they have to be used for the addressing or can Function 10 be used. Still cant get Altivar to run, the error word W221 in the programme reads 103 and 203 which is the Read address is this where the problem is. Will try again tomorrow. It must be wonderful when it finaly runs. Regards Peter

[PMCR 66]

Lost Control appears to be on the correct path! The addresses in the ATV31 document appear to be in decimal, but Modbus need them in HEX. The other thing you may try doing is subtracting 1 from the Modbus address. Some manufacturers document the address, but the Modbus mapping is really 1 less. The other thing you could do would be to use CX Protocol and do a trace of the serial port. This would show us exactly what is being sent and returned from the drive (if there is a response). The .pdf below shows the steps. Save the Protocol Macro file, and then post when you are done. The data that you trace is saved as part of the file. CX Protocol Data Trace.pdf

[lostcontrol 23]

Hex #10 = Decimal 16, which is preset multiple registers, so Function 10 should work. It may be worth doing what PMCR suggests re the address offsets, but I am pretty sure with Schneider that these address's would be correct. You should definitely be getting a response. Question: Have you programmed the ATV31's to be the correct Node address's, 1 & 2? I would be starting with just a single drive first, & make sure that will work. The trace data will be useful as well.

[denise01 3]

Hello PMCR and Lost Control, Still cant connect to Altivar I am 99.9% sure Altivar side is okay. Looking at the response programming o103 and 0203 were showing as faults so I take it not being Read on modes 1 and 2 function 3 I have enclosed a trace and also email from Schneider Technical help. My theory is that the settings inside the SCU 31 v1 are wrong. If I upload the IO table from the programme it will show the correct settings. But when I connect the CX Protocol and click IO table then there is no IOs table showing any cards. I read the Protocol manual and it said go on line click Create and you should be able to create a table. My question really is is the PLC programme and the Protocol programme linked. One gives the CX Programmer name but the other just says CJ1M PLC. Do I have to link the two somehow. Bit confused. I honestlt think that this is the sticking point. The good news is I can nearly understand most of the programming and addressing. Regards Peter Schneider.doc

[denise01 3]

Sorry cant send Trace as I dont have Protocol at home it was just a flat line though

[PMCR 66]

I just took a look at the port configuration for the SCU module. The first setting for Port 1 is Port Settings. If you leave this at 'Defaults', it ignores all the other settings that you make. It appears as though this is the case for your project. Set Port Settings to 'User Settings'. Also set "Maximum Number of bytes in Protocol' to 1000 to allow the maximum receive buffer size (this is not the problem). Look in the manual for the Modbus Solution (page 6) for the setup of the port. Set the port exactly as shown, and download the settings.

[lostcontrol 23]

Yes. Edited 8 Sep 2012 by lostcontrol

[PMCR 66]

denise01 If the port on the SCU card is not configured correctly, nothing will work. Configure the SCU card through the IO Table tool. There are 2 places to create the IO table for the PLC: CX Programmer and CX Protocol. Create the IO table in CX Programmer. Here are the steps. 1. Go Online with CX Programmer. 2. Put the PLC in Program mode. 3. Double Click on the IO table (from the tree view). 4. Click Options / Create. 5. In the Dialog Box that asks 'Are you sure you want to create the IO table', click 'Yes' 6. In the Dialog Box that asks 'Initialize CPU Bus Settings', click 'Yes'. 7. In the Dialog Box that asks what to transfer, leave both boxes checked and click 'Transfer'. 8. Once the IO Table has been transferred, click OK. 9. Click the '+' sign next to Main Rack. 10. Double Click on the SCU31 card. 11. Make the settings as shown in the manual for the Modbus Master program. This is also shown below. 12. Click "Transfer PC to Unit'. 13. In the dialog box that asks 'Are you sure you want to continue', click 'Yes'. 14. When the transfer is finished click 'Close'. 15. In the dialog box that asks if you wish to restart the module click 'Yes'.

[denise01 3]

Hello PMCR, Lost Control, I messed around with the programme today, did the SCU 31 Card as advised. I managed to get rid of the alarms in the Response section. I also managed to get a good trace which showed a red line so progress . I have posted the programme. I still cant get the Inverter to run. The Shneider guy said that basically I need to read the status ETAD Register and send the appropriate output to the command CMDD I gues this is in the run section of the programme but not sure what needs to be done. The bit is sent to D6004 when a start signal is sent but not running. I posted his comments. I feel that I am nearly there just something wrong in the PLC Programme for running it. Regards Peter PS I take it that the run signal comes soley from the modbus signal. ATV31-CP1LCP1HCJ1CJ2CS1ModbusSolutionV080912_latest.cxp

[lostcontrol 23]

There is no difference in that programme to what I posted? You need to post a copy of the trace from CX-Protocol, as well as a wiring diagram showing all connections & switch settings, including PLC unit no's.

[denise01 3]

Hello Lost Control, The only thing I changed was the read write section. So not sure whats different. I am just testing the Altivar 31 on the bench just a 415 volt connection to L1, L2 and L3 and one PLC with a SCU 31 V1 card. Do I need to put a 2 wire connection to L1/11. Will try to download CX Protocol Regards Peter

[denise01 3]

Hello Lost Control, At the moment I am bench testing the Altivar 31. I have connected L1,L2 AND L3 to Altivar. Could you please tell me what the setting of 500 is that is moved to D6005 in the Control Section. Also do you have an email address I can post the Trace to. I dont have Internet access at work but I do have email and CX Protocol. Regards

[lostcontrol 23]

I will PM you my email address.

[denise01 3]

Ok Thanks Lost Control

[Roberth 2]

Hello! you could make the Altivar 31 communication with the omron cj?

[Roberth 2]

I need to report a CJ2 with 18 Altivar 31 per modbus!

[lostcontrol 23]

You will need a SCU module, I would suggest a SCU31, as this has 2 RS485 ports. Depending on what sort of response you require, I would consider splitting this over 2x networks.

[PMCR 66]

The latest version of the Modbus Master code at the link below supports 2 simultaneous modbus ports. http://forums.mrplc.com/index.php?app=downloads&showfile=867

[Roberth 2]

But I have to create a file and CX Protocol. To achieve communication.

[lostcontrol 23]

Not really, the Modbus function that PMCR has linked to has the file already created, all you need to do is download to your CPU...

[Roberth 2]

I will test this week and you communicate.