Iam trying to use Aurdino Uno to communicate with the Selec energy meter, using MAX 485 IC Please help
As you don't seem to have a problem with the IDE, your topic has been moved to a more suitable location on the forum.
How far did you get? Where are you stuck? Please provide a wiring diagram how everything is connected? Do you have a description of the protocol used by the Select energy meter?
Thanks for the response..
Energy meter : Selec MFM384-R-C
Protocol : RS485 and Modbus RTU
i have got the diagram from forum only and still iam collecting the more information before starting. If you have any circuit and code share me or elese suggest me any other ways.
I'm not familiar with Modbus RTU. Have a look if there is anything useful in arduino modbus rtu library - Google Search.
https://www.selec.com/viewdocument/a96d3afec184766bfeca7a9f989fc7e7 has a list of the registers.
And that is probably how far I can help you.
Here's a diagram of how to connect a soil sensor to an Arduino UNO using a MAX485 module. The sensor is also a modbus device.
The diagram also shows how to connect a PC with a USB-RS485 dongle to monitor the RS485 bus for debug purposes.
Has the meter already been installed in your building, complete with the necessary current transformer(s) ?
Bro,
Iam not getting PC and Sensor , RS485 Dongle here, can you explain little bit deep.
Yeah,
Already installed.
Which part of my diagram are you having problems with?
RS485 Dongle and Sensor. Because in Selec energy meter we have 2 output cables, that connects directly to TTL to RS-485. But i am not getting which sensor ?
I think that ithejjala wants to see a diagram that is specific to his requirements, rather that the more generic diagram that you showed him, which has a soil moisture sensor and not an energy meter.
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The RS485 dongle and PC are a nice to have that will help if the Comms do not work correctly.
Are you referring to the A & B signals of the RS485 bus?
Perhaps it would be easier to assist if you could show a diagram of what you have so far - a hand drawn one is fine - photograph it and upload it here.
Do you already have an RS-485 to TTL adapter ?, such as this one :
I noticed from the MFM384-R-C manual that the RS-485 terminals on the energy meter are labelled '+' and '-', rather than 'A' and 'B'.
There is supposedly a standard that says that the 'A' terminal is '-' and the 'B' terminal is '+', but that isn't always the case.
If you have a multimeter you could check the polarity of the 'A' and 'B' terminals.
You might have to get the polarity right by trial and error, only one way will work, but no damage will result from getting it wrong.
Sorry, but I can't help you with the Modbus Protocol.
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