RS485 Question

[Dgocof]

We have 2 Fuji temp controllers and are trying to connect 3 Invertek variable speed drives for Drum, stirflex, Airflow and control them with Artisan via buttons. The question is, can these be setup on two separate daisy chains using the same serial port communication in Artisan. Can this be achieved with a hub? How can we achieve this? We are using the latest version of Artisan on a windows laptop.

[roasterdave]

Artisan supports one RS-485 interface.

No idea if the approach in this discussion will work or if was tried. Let us know if you find an external device that works for you.

[Dgocof]

With the two Fuji's set up already and adding the VF drives to the chain do we have to set up the VF Drives in this screen also or can we we just write commands to the drives via buttons or sliders and address them from there after we have assigned them different slave numbers?

[MAKOMO]

Well, the situation is a bit more complex. Artisan actually (still) reports two RS485 networks.

There is still a very early implementation of RS485 for the FUJI/Delta PIDs which exclusively works for those (if PID is selected as main device and not Meter and "Modbus Port" is not ticked in the PID device configuration in the ET/BT tab of the Device Assignment dialog). This implementation is very simple and specific for those PIDs, works only for the two main channels ET/BT and might be removed in future versions of Artisan. This one uses the serial port configured in the ET/BT tab of the Ports Configuration dialog and not the serial port set in the MODBUS tab. This RS485 implementation operates completely separate from the regular MODBUS device type which is configured in the MODBUS tab of the Ports Configuration dialog. However, if that flag "Modbus Port" is ticked the modern MODBUS implementation is used for communication and the serial port configured in the MODBUS tab is used. Confusing!?

Thus it is possible to run two separate MODBUS RS485 rings with current Artisan versions. One exclusively for FUJI/Delta pids using the historic (to be removed) MODBUS implementation connecting to the serial port configured under ET/BT in the ports dialog, and a second running the modern MODBUS implementation configured in the MODBUS tab and connecting to the serial port as specified in the MODBUS tab.

NOTE: to send a command from a custom event button to the FUJI/Delta RS485 ring you need to use the FUJI Command write which can only be used to write a single 16bit register.

In case you have your Fuji PID up and running fine using the old-style PID Modbus implementation you can add a second RS485 using the modern MODBUS implementation connecting your frequency drives and controlling them from buttons using the MODBUS Command actions. Alternatively, you can connect your Fuji PIDs also to the RS485 ring containing your frequency drives and read/control all devices from the modern MODBUS implementation.

Hope this helps doesn't confuse you too much

[Dgocof]

Makomo I think I understand. I have the Fuji's running in meter MODBUS now controlling a modulating gas valve. It works great! I also have buttons to control the gas % manually when needed.
I don't want to switch them to PID in device assignment especially if it may be discontinued at some point. I think the best way to address the E3 drives is to daisy chain them to the Fuji's on one RS485. Although the Fuji's are 2 wire and the Invertek drive is three wire daisy chain, Not sure how this will work unless we move the Fuji's to slave 5 and 6 to wire the Invertek drives first if it indeed needs three wires to the RS485. connector.
My question is can I address the drives with a_ write(3,1,500) _50 hertz on salve 3 register 1, with a button or is there additional setup needed in ports configuration for communication to the drives. My present ports setup for Fuji is above.
I'm also not understanding your statement : if that flag "Modbus Port" is ticked. I couldn't locate that.
Thanks

[Terracotta-6]

I have the Fuji's running in meter MODBUS now controlling a modulating gas valve.

Could you share the specific model of the gas regulating valve you adopted？

[Terracotta-6]

Modbus Port

[Terracotta-6]

My question is can I address the drives with a_ write(3,1,500) _50 hertz

Register address 2 for frequency regulation.

[Dgocof]

[Dgocof]

Thanks for clarifying.

[MAKOMO]

My question is can I address the drives with a_ write(3,1,500) _50 hertz on salve 3 register 1, with a button or is there additional setup needed in ports configuration for communication to the drives. My present ports setup for Fuji is above.

Yes, should be possible. Just choose "MODBUS Command" as action. Note, however, that the write command is deprecated and will be removed in a future version. Use writeSingle instead to write to one 16bit register or use writeWord to write a float to two 16bit registers.

[Dgocof]

[Dgocof]

Marko or anyone I'm wondering if we are going to have trouble with our modbus chain because our Fuji's are 2 wire modbus and the Invertek drives are 3 wire with a common? Is there a workaround?
We are able to write to the drives now with an event button writing to register 1 not 2. Invetek helped us with that along with chat gpt.

[Terracotta-6]

Fuji 是 2 线 modbus，而 Invertek 驱动器是 3 线通用的？
Connect the data Modbus RTU -RS485 +RS485，Note that the addresses of the master and slave sites must not conflict.
The discussion content has gone beyond the scope.

[Dgocof]

We were able to communicate easily in modbus with the two wire and three wire communication all in the same chain. We were sent down a rabbit hole by the Invertek folks with converters and special wiring. We just had to keep the positive and negative aligned.