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Modbus RTU data does not match real time data from sensor
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If the flow rate is represented as a floating point number, then you will be reading 32 bits of...
By Dan on 28 February, 2010 - 1:35 pm -
a) I tend to expect a flow rate that jumps around. Is the meter installed in a line with such a...
If you are getting data, even if it is goofy, at least you're addressing is valid, even if it isn't...
By Russ Bartels on 28 February, 2010 - 12:33 pm -
Sorry, no answer, but a suggestion.
Check to see if either the master device or slave has an...
By Roy Matson on 28 February, 2010 - 10:06 am -
Raymond
Have you got the baud rate etc. correct, sometimes if it's not quite on the data can...
By Raymond on 28 February, 2010 - 3:24 am -
Hi Carl,
Thanks for the reply. I am using signed and float to read the register. The number is...
By Carl on 27 February, 2010 - 12:04 pm -
>The address for flowrate is 8 = 928... <
What do the dots after the 928... mean?
What...
connecting my older Honeywell 620 controller to a modern Operator Interface using a converter
from the Automation List department...
Receiving data from a weighing scale using RS232 with VB 6 AppI have a digital weighing scale I need to connect to the PC using RS232 communication port.
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By M Griffin on 27 February, 2010 - 9:39 pm -
You will need the Pyserial serial port library. If you are using Linux, it is usually in your...
By PG on 27 February, 2010 - 10:01 am -
Hiya,
you may be able to help me, basically I need python scripts to help read a voltage...
By Ali on 24 February, 2010 - 11:46 am -
Dear Sir:
I read your post. on 16 February, 2007 - 11:03 pm. You told another person how to...
Losing data using freeport communication
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By Mark on 27 February, 2010 - 8:13 pm -
Hello,
What is the frequency the device is sending to the S7-200? I have seen cases in which the...
I want to talk to a Zelio Logic Relay with the SR3-NET01BD Ethernet/Modbus/TCP/IP module. (Schneider Electrics)
Problem with Ethernet communication between a TSX premium TSXP574634 and two supervisors OpenVMS
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By Ricardo R on 26 February, 2010 - 3:32 pm -
Hello again,
I only send new post to know if somewhere who work with Schneider PREMIUM can help...
Hour meter that have some sort of output to send to PLC or via comms
Can a Magelis Display Panel be connected to the Twido RS-485 Programming port?
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By Schneider Brazil on 26 February, 2010 - 12:32 pm -
What is the reference of the Magelis ? There's different cable references for each type of HMI.
...
how to calculate baud rate's of RTU
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But maybe your real question is how to calculate the maximum data throughput.
This is a...
By Dick Caro on 26 February, 2010 - 9:33 am -
You are technically correct according to the IEEE 802.2 Ethernet standard - BUT that only applies...
By M Griffin on 25 February, 2010 - 5:07 pm -
If you are using 100base-t Ethernet, then the Ethernet baud rate is 100 mega-bits per second. That...
By amir mohammadi on 25 February, 2010 - 2:24 am -
what charachter's affect on calculation of baud rate if we use ethernet 100base-t layer2?
is there...
Can I send text strings over modbus RTU
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If the HMI supports it, you could use the Modbus Read Device Information command (function 43/14),...
We have definitely done this in the past on controllers we have designed. All we did was define a...
I don't think the maximum packet size would be a limitation. After all, Modbus is really just a...
By M Griffin on 24 February, 2010 - 4:47 pm -
You can simply put characters in a series of consecutive registers, with one or two characters per...
By John Correa on 24 February, 2010 - 4:35 pm -
Yes. I'm not sure what type of PLC you are using but if this data is not available through modbus...
By Fred Loveless on 24 February, 2010 - 2:26 pm -
It really depends on the device and the communicaitons software. Strings are just byte arrays. You...
By David on 24 February, 2010 - 1:30 pm -
Theoretically, yes,
a) if you have the ability to write custom programming, but you'd have to do...
By jc on 24 February, 2010 - 1:15 pm -
Strings are commonly sent over modbus. Each 16bit register can hold two 8 bit characters. ...
fixing stereo preamp. I suspect a rs485 chip failure
Need for technical manual of Elektronikon MKIV controller from Atlas Copco
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By ETURU on 25 February, 2010 - 2:06 am -
Hi,
first of all you have to buy a communication module for profibus, modbus or others at Atlas...
Can we use slc 5/04 or SLC 5/03 processors with AB's plc 5 systems
Socomec control vision error
IEC 101 Master Simulator and information about the IEC 101 Protocol
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By Bill Tarlinton on 23 February, 2010 - 9:50 pm -
Hi Siva,
not sure if this is any help, but we have an IEC870-101 and 104 slave simulation tool...
problems configuring a modbus RTU slave to communicate with MarkVIe
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I've been watching this and other posts by this originator, and it's just not clear what...
MarkVI can only be used as a Modbus slave, not as a master, if you buy the opc servers separately...
By capriconian on 23 February, 2010 - 10:44 am -
Actually the client want to it through the controller. Otherwise using an OPC is good option. In My...
By Wassim Daoud on 22 February, 2010 - 11:31 am -
Have you tried to use OPC for this? Download OPC Server for Modbus:
...
Communication between Yokogawa DCS System and Siemens PLC through Profibus DPV1
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By Hamid on 23 February, 2010 - 6:10 am -
I did the profibus communication between Yokogawa and Siemens DPV/DPV1. if anybody need info/help...
serial communication in visual basic using mscomm control
Field Bus - Profibus Concept
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By Dick Caro on 22 February, 2010 - 9:44 am -
The short answer is YES. You will need field instruments that are capable of running Profibus-PA...
how to manage Modbus with iPhone?
Any ideas for an entry-level DNP3 & DNP3 over IP PLC?
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By Terry McCulloh on 22 February, 2010 - 8:06 am -
Opto 22 supports DNP3 level 2 slave in serial and IP.
Please check our WEB site...
I am looking for a way to be able to communicate via ethernet with S7 plcsim and Software Toolbox's Top Server.
Is there a difference between the physical layer of the SPA-rear port on the ABB REF542 and REX 521 relays and the conventional RS485?
Low cost power meter-data acquisition.
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By William on 21 February, 2010 - 9:07 am -
We do offer such very low cost modbus meter, please feel free to contact us: http://www.stitcs.com...
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