Master & Slave

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lawrenceb
Posts: 4
Joined: 02 Mar 2017, 15:57

Master & Slave

Post by lawrenceb » 02 Mar 2017, 16:03

I am looking for advice on setting this system up.
I have 2 Keller pressure transmitters with RS485 outputs going into ports 2 and 3 on an ACM board, I therefore require the CMC to operate as a master however, the CMC is outputting to an Exemys GRD and therefore operating as a slave.
I have 2 PT1000 also going into the CMC and have already got the CMC to GRD side working but cannot work out how to set up the logical channels for the pressure sensors.
Can anyone help?

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multicon24
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Posts: 164
Joined: 24 Oct 2012, 20:59

Re: Master & Slave

Post by multicon24 » 03 Mar 2017, 11:21

Dear Customer,

If Keller pressure transmitters are communicating at the same parameters, and their addresses are different, you can use one RS485 port to connect them both.
To use channels to show values from Modbus, you need to set them into Modbus mode. Please see this videos:
https://www.youtube.com/watch?v=ZJvHa4LmiFg
https://www.youtube.com/watch?v=0I3qGsKuXpQ

They shows general principle how to configure CMC to read data from SLAVE Modbus RTU device.

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Maciej Mitura

lawrenceb
Posts: 4
Joined: 02 Mar 2017, 15:57

Re: Master & Slave

Post by lawrenceb » 06 Mar 2017, 12:17

Hi Maciej

Whilst I could reprogram one of the sensors to a different address, it is just as easy to use both ports, one for each.
The current unit is showing as a Holding register 40003, 32 bit floating point (2 x 16 registers)

So I have put into the CMC, set to Holding, register 3, 32 bit fp, (2x16) but still get an error on screen.

I can't upload the .cfg file as the forum wont allow it

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multicon24
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Re: Master & Slave

Post by multicon24 » 06 Mar 2017, 12:32

Dear Customer,

In general your configuration is fine as you described it. Please send cfg file to support@multicon.eu.
Also try to read register #4 as different producers use different offsets.

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Maciej Mitura

lawrenceb
Posts: 4
Joined: 02 Mar 2017, 15:57

Re: Master & Slave

Post by lawrenceb » 06 Mar 2017, 13:09

Maciej

email sent with config

Thanks

Lawrence

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