Internet PLC Forum

Hi Gary,

I agree and I will investigate further.  

I have a a bigger issue that I need assistance from ASAP.

I have been trying to set the PLC ID's  using the Trilogi software and for all the r78A, r77 and some of the r76A's no problem however, on four PLC's with FW r76A are behaving very erratically.

When I changed the ID the PLC rebooted but from this point I was unable to re-connect to the PLC via the ethernet port.

I went to the PLC's, I expected a re-boot would solve the issue but it didn't.

Some of the PLC's had the pause LED on, some had the pause LED and the run error LED on.   Despite reloading the program locally via the serial port I could not gain any access to the ethetnet port.  I couldn't even ping the PLC.

I used the TL server to check the ID and it was as per what I had set from the ethernet port as above pre-crash .  I re-set the PLC to ID of 1 and instantly the problems disappeared and the ethernet port was responsive again.  - HELP!!!!!!!!!

I have a small HMI on the RS232 serial port looking for an address of 1 and a power meter on the RS485 port which I can can change to match the ethernet port ID if need be.  However i cannot do this if the Ethernet port turns off if the ID is not 1!!!

I guess I need a work around for changing the Ethernet port ID to any number other than 1 or the FW to make all my PLC's r78A as the flexible setsystem command would work a treat for me on this application.



PLEASE HELP ASAP

Morning,

This now works from a fixed hex ID i.e.

SETSYSTEM 8,&H03FF ID is changed to FF.

Going back to my initial post, how can I set the ID via the DM field value?

SETSYSTEM 8,&H03 + DM[66] compiles ok but doesn't change the ID

Hi,

Some of the PLC's are r76A but the code still doesn't work?

Cheers

FYI,

FMD16 FW r76 I think

Cheers

Hi Gary,

Yes I tried that but the PLC does not change the ID to the value in the DM field so i figured it needs to be in hex?

FYI we have a lot of PLC's on a site in Scotland (20 ish) and they all auto ID themselves based on the IP address.  All this does is take the last three numbers from the IP address and place the value into DM[65].  The HMI and webpages displays this value as the panel ID.

I did this so I can use one version of software for the whole site and it works very well.

My problem is the main site HMI wants to see each PLC have a different ID even though they are different IP addresses.

I thought I could use my auto ID code to also set the PLC ID via the setsystem command so I set this up on a first scan function but the PLC ID remains at 1??

Cheers

Hi,

I used the example which works but yours is more efficient so thanks again!

B = ADC(1)
B = (B - 819)*2600/3277

Hi,

I'm trying to read a PT100 via a 4-20 converter but i'm getting the wrong reading.

The converter is scaled 4-20mA, 100Ohm to 198Ohm = 0 to 260 DegC.

I process the 4-20 via a 250 Ohm resistor to get 0-5V

as I see it 260 / 5 (0-5V input) = 52

B = ADC(1)* (2600+520)/4096 - 520

but to get a sensible reading I need to use 650 not 520 but I cannot calculate why??

B = ADC(1)* (2600+650)/4096 - 650

The usable range of the input is 1 - 5 Volts = 0 to 260 deg C as the converter sends out 4-mA as a minimum so I guess this is where my conversion is going wrong!

Any thoughts?

Hi,

We use the FMD 16 PLC for a control system and we also utilise the web server function, both work well.

We recently supplied some additional panels which have the same PLC in each but the PLC FW in one panel was r77 and r78a on the other.

The PLC program works the same on both but the web page on the PLC with the later FW shows an asterix (*) on the LCD at the end of the LCD line text see pic.

Any ideas?