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How many energy meters can I put on one USB Port of the Cerbo via an RS485 to usb cable assuming I've given them all different ascending MODBUS ID's
I've got an RS485 daisy chain on one USB port with three devices on it but for some reason the Cerbo only sees 2 devices. Plugging that same USB cable into my laptop and viewing via Carlo Gavazzi's software all three shows up no problem and comms is good.
Please assist asap.
hi,
as far as i know its limited to max 2 energy meters, (only modbus adress 1 and 2)
What I'm seeing is Address 1 gets displayed on the Cerbo constantly, Address 2 is erratic, and address 3 is gone. interchanging Addr 2 and 3 makes it show the new addr 2. Telling me your hunch is correct, but where is this indicated in documentation?
And why is address 2's comms so intermittent?
Will I have to run two more RS485 to USB cables with a USB extension hub? or can I put the mains meter on the 1st RS485-USB and program the other two PV Inverter meters as addr 1&2 and hope it doesn't repeat the errattic behaviour?
Same problem Here but with ABB meters
https://community.victronenergy.com/questions/199015/cerbo-modbus-rs485-rtu-connection-abb-b24-meters-a.html
Hi,
please take a look at this documentation: https://www.victronenergy.com/media/pg/Energy_Meter_EM24_RS485/en/installation-and-configuration.html#UUID-7ea0412e-1ca1-db77-7da4-2a2a548f6189
In fact only 2 meters are possible per RS485-USB connection.
For more than two meters (to my understanding) you need a separate RS485 USB adaptor AND also a separate USB port (so no hub possible in this case).
In my installation I am running an EM24 and an ET112 on one RS485-USB connection without problems (So no erratic behaviour as described by you).
Regards
Alex
Hello,
Can I change the ID on an ET112 ?
Hi,
yes you can do that. But since ET112 has no display, you will need a configuration software from Carlo Gavazzi to change the ID:
https://www.gavazziautomation.com/nsc/HQ/EN/product/ET112DINAV01XS1X
Download the ucs.zip configurator on this support site. You will have to connect the ET112 to your PC, ID cannot be changed directly via the CGX.
In my case I was using EM24 and ET112 on one cable. I changed the ID of EM24 (since this one has a display and can be done easily via the small "joystick") and I left the ET112 on default.
Nice ! Thanks a lot
Is there a way to hack this 2 meters limitation? I don’t see a reason for this. Rs485 can easily handle many more devices. Maybe we can edit some .py script to scan more addresses? EM24 seems to have no limitation (scans whole subnet).
Can someone confirm?
Thank you for your thoughts.
