BobB

Thanks Michael - yes - memory has been moved and expanded to E.

I normally use the PMCR system for Modbus RTU reads but have an absolute heap on this job I am working on (4 serial cards - stuff from everywhere) so have decided to use the function block method - it will be easier. Attached is a file which is my method that I hope will work for a small part of the job. I have used a counter to step the reads and a bit counter to count the done bits and step the counter on to the next read. Not sure if this will work but assume that when a done bit turns on and the counter moves to the next read the done bit will turn off and then when the next read takes place that done bit will turn on and step the counter again. If any of you have used this before would you mind checking my code please. If it will not work I do not want to be programming a heap of stuff that will not work. Thanks for any comments. Modbus Sample.cxp

Ta.  

When editing rung comments in CX-P how do you wrap text to the next line? Line is getting too long and text needs to start on the next line. Like this LOL. Enter does not work but closes the dialog window.

Oooh - no takers? Surprised. Michael Walsh?

https://www.myomron.com/index.php?action=kb&article=1243

I understand Advanced HMI has an Omron driver.

Use the Modbus function block as above - it works with a bit of manipulation.

I strongly recommend using ANDW as described for separating the time segments - I use it all the time.It is seamless.

Raw CIP - eeek! Last time I did that was donkey's years ago on Device Net. Not for the faint hearted. Do not even have it now - old computer crashed.

MOV &0000 D100 will clear it.

Michael - thanks - will give it a go.

The only thing I can find in help re using the buzzer is to use a multi function button. I want to use the buzzer as an alarm buzzer and turn on $SB13 or $SB14 from a bit in the PLC. Can anyone help please?

Michael I did not enable run as I do not need it. I did enable basics and from the initial value page tried to enable bit 14 but it will not enable - will not turn on. That is what I was referring to.

'err' to 'on' - where? I thought from the page checking basics and the selecting on or off would do it but cannot select on.

OK - tried it out today. Selected basics but it appears one has to click on each individual item to enable ii "on" or "off" - cannot click on these at all and enable them. $SB has been allocated to channel 700. Turn on 700.14 in the PLC and nothing happens.

figured it out mate - will be onsite doing tomorrow. Will let you know how I go.

Ta chelton - found it.

Hi lostcontrol - do you mean as in a macro or something like that?

Silly question time. I am looking at a job where I will have to use Hirschman or some other brand of switch for Ethernet IP I/O that will form a ring - they are about so that is OK - have done it before. The other issue is that I have to have 2 x PLCs in 2 different cabinets on the network. Each will be in the ring and the standby PLC will have a dry contact input from the duty PLC to turn the outputs off - warm standby. They will not accept the CS1D as there is only 1 rack in 1 cabinet. Question is can I have 2 PLCs scanning the Ethernet IP I/O at the same time? I can see no reason why not but may be wrong. Another issue I would have is that there is to be monitoring by a BMS system Modbus TCP. Each PLC would have an Ethernet card with the same IP address which would cause a clash on the network. Is it possible to make the Ethernet card in the standby PLC 'invisible' while in standby mode when the dry contact is on from the duty PLC and then when the dry contact turns off make it visible and make the Ethernet card in the duty PLC 'invisible'? Schneider do this internally in the M580 hot standby system. My only other option is the very expensive Schneider M580 system. Any help appreciated.

Thanks Michael - I think I will have to go to a dedicated PLC for this unfortunately. Schneider have the M580 and Emerson appear to have one as well. Will investigate further today.

Sadly I did not know Jay had passed away. We have had discussions over a long period of time - since I joined this group actually. I have run Ethernet switches in a ring before - no issue there. Will have to dig further I guess. Thanks.  

Will rephrase - original post is all over the place like a mad woman's breakfast! Old Aussie saying. I want to put 2 x CJ2M processors on the same Ethernet IP network - both will be scanning - they will have different IP addresses. I will have to use a standard CJ2M and an Ethernet IP card due to the final configuration - too many drops for the onboard Ethernet IP - over 16. Each PLC will also have an ETN card for access by a building management system via Modbus TCP - need the ETN for that as the FB uses sockets. A dry contact to go from the duty PLC to the standby PLC to disable outputs but not disable scanning. Also need to disable the Ethernet card as both ETN cards will have to have the same address eventually for the building management system. When the duty PLC is in control its ETN card will have address 192.168.250.3 for example. If the duty PLC falls over the standby PLC ETN card will also need the address 192.168.250.3 for the building management system. It would be possible to write the address to the DMs for the IP address but the problem I see here is the rotary switch on the front of the ETN would have a different last octet number than the number written to the DMs and would cause an error. Is it possible to turn on a bit to tell the PLC to ignore the rotary switch so there is no error? Also is it possible to have 2 x CJ2Ms in the same Ethernet IP ring scanning all the I/O? Eventually there will be 23 x Ethernet IP drops back to the processors. Michael Walsh? Jay Anthony? Hi old fella from another old fella.    

After reading some more documentation it appears that the M580 actually swaps Ethernet addresses to N and N+1. Is there a way to do this at all please?

You will not - that was in 2006!