Posts from...
Today, Thursday, October 23, 2014
Originally posted by Ben Herston on 21 October, 2014 - 5:54 pm
I need assistance in programming a Modicon Bridge/Mux BM85S485. The product is obsolete, and Schneider no longer provides technical support.
New Replies:
This pdf appears to be the manual you are looking for:...
By Lynn August Linse on 22 October, 2014 - 10:13 am -
Do you mean you are actually looking to put custom code on the BM85? It has been a long time, but I...
Give me an email address and I can mail you the user manual that explains the whole module....Don't...
Topic: Software, including programming, OS issues, etc.
from the How far can I stretch the standard department...
How Strictly Should the MODBUS Addressing and Data Models Be Followed?
Originally posted by MikeAtCalidus on 16 October, 2014 - 5:50 am
How flexible can the Addressing and Data Models be with regard to the width and alignment of objects accessed through read/write register functions?
New Replies:
Hello, My point was: follow the specification. Regards, Mark http://www.peakhmi.com/...
By Lynn August Linse on 20 October, 2014 - 12:27 pm -
Mark, I can only shrug, reporting what I've seen. As I said, I find it annoying, and do as I...
Hello, What if the master uses two reads and the combination of two reads fetches the complete...
By Lynn August Linse on 20 October, 2014 - 9:30 am -
I have seen small products demand a read starts at 'beginning' (offset 0). I've also seen products...
Considering the answers above, would it be acceptable for the server to respond with an ILLEGAL...
Hello, >...is it more likely to make people reject the product as being utterly...
> Would a Modbus server with register greater than 16 bits be useable? No, It would be a...
Topic: Software, including programming, OS issues, etc.
from the Forum department...
Maximun nodes of Modbus
Originally posted by Kevin Fan on 14 October, 2014 - 10:18 pm
What are the maximum nodes and cycle time of Modbus TCP and Modbus RTU on RS485?
New Replies:
By Patrick Lansdorf on 16 October, 2014 - 3:03 am -
Hi Kevin, I guess that for Modbus TCP there is no real limit of nodes. If the subnet mask...
Topic: Human-Machine Interface and SCADA.
from the Engineering department...
HMI Communication with SIEMENS PLC
Originally posted by Ali Shakarami on 2 October, 2014 - 10:23 pm
Sending the signal value from GE HMI(CIMPLICITY) to other controler over MODBUS RTU
New Replies:
By Patrick Lansdorf on 16 October, 2014 - 2:39 am -
Hi, You will need to check what type of Siemens PLC it is. If it is S7-1200 or S7-1500, you...
The answer is yes. You can transfer signals over the modbus with your HMI. The problem is that...
Topic: PLCs and related questions.
from the Forum department...
MSTR TCP/IP Control Word Definitions
Originally posted by Jon Pope on 16 April, 2009 - 4:20 pm
clear definition on some of the control words used in setting up the MSTR function with TCP/IP
New Replies:
Hi I came across this post tryign to find answer to an issue using the same configuration u...
Originally posted by connected on 14 September, 2014 - 2:31 pm
Problem with SCADA system that supervises electrical power flow for a residential building. Connected with Modbus RTU over RS485 daisy-chained 2-wire. The communication on the bus seems to be destroyed with Schneider PM750 connected.
New Replies:
I finally found a solution to this problem. Based on the response here, I've measured the...
Thank you for your kind and relevant responses. I've been approaching the problem with biasing...
I've seen similar problems a few times before -- where one device brings down the RS485 bus. One...
> By the way,, does it exist any utility to check the serial interface of the Pm75? I'm thinking...
By Lynn August Linse on 18 September, 2014 - 4:08 pm -
If you expect lightning/grounding damage, what I have done a few times is power everything off...
I've been researching this problem today and tried both biasing of the bus, different common/shield...
This link shows the shield connection to the PM750: ...
> Where are the terminating resistors and what value? Resistors are placed at the cable ends,...
> It is most likely a grounding issue - that the 2 vendors approached the 'reference signal to...
Two points: 1. RS485, technically speaking, is a 3 wire system, A, B and COMMON. But the...
By Lynn August Linse on 15 September, 2014 - 9:51 am -
It is most likely a grounding issue - that the 2 vendors approached the 'reference signal to...
Topic: Motion control, servos, steppers, etc.
from the Electrical & Systems department...
Over-speeding of Slave Motor in Rock Conveying System
Originally posted by Ravindra K Maheshwari on 28 September, 2014 - 6:16 am
Rock coveyor is being driven by Master and slave, two motors in load sharing mode. Slave motor is over-speeding when master gets higher loads.
New Replies:
Is there the possibility that despite the use of VFDs, the motors are locking up at full voltage? ...
Topic: Programming languages.
from the EIC department...
Modbus TCP / IP Query
Originally posted by PLC_EIC_Bloke on 12 October, 2014 - 8:07 pm
Setting up Modbus TCP/IP with a single slave and no unit ID
New Replies:
Cheers Lynn I had a feeling that is how it would work as I definitely tested it before without...
By Lynn August Linse on 14 October, 2014 - 10:52 am -
The 'officially' sanctioned modbus.org answer is to use 0xFF (255), which means 'this is an IP...
It seems most manufacturers in that case set slave_adr = 1 as default value. Try communication...
Originally posted by Heru Iqbal on 30 March, 2014 - 12:49 am
After you read this thread, Now you can create your own HMI by using Microsoft Excel and HINET Modbus DDE Server.
New Replies:
MODERATOR'S NOTE: If you do this please let us know how it works. Thank you ...
Topic: Communications systems and equipment.
from the Forum department...
Modbus frame size
Originally posted by Bin on 6 August, 2009 - 5:25 am
Can I use the Modbus frame size larger than 256 bytes?
New Replies:
What happen if you request more than 125 registers? will Modbus device send out two response...
Topic: Communications systems and equipment.
from the Forum department...
Modbus RTU with Star Topology
Originally posted by JulienN on 8 October, 2014 - 3:42 am
Does the Modbus RTU work with a star topology?
New Replies:
Star topology will work but stability can't be assured for a large network like yours....
Topic: Communications systems and equipment.
from the CONTROL department...
ESD thru MODBUS??
Originally posted by PANDU on 8 February, 2012 - 1:17 am
Is ESD thru modbus is ok??
New Replies:
>I don't think so speed is the only >issue it can be another thing like :- >comm...
Topic: Motion control, servos, steppers, etc.
from the Industrial Automation department...
Modbus TCP/IP
Posted by Mikey on 7 October, 2014 - 5:41 am
Developing Modbus TCP/IP on RX63NB board with DP83620 as PHY layer interface.
Originally posted by Nizam on 1 October, 2014 - 9:01 pm
Allen Bradley Micrologix 1400 PLC Communication with Yokogawa DCS
New Replies:
AB does a pretty good job of making the answers to those questions available in their documentation...
Topic: Software, including programming, OS issues, etc.
from the Forum department...
Adding Modbus register values together
Originally posted by David on 20 August, 2014 - 3:07 pm
How can you add MODBUS registers?
New Replies:
I have a solution in which you will also have a display of the values and the sum. Using our...
Topic: Communications systems and equipment.
from the Master Thesis world department...
Master Thesis Guidance With Protocols
Originally posted by Sandra Calvo on 26 September, 2014 - 3:56 am
Trying to decide which communication protocol is better for the API I am designing for my Master Thesis.
New Replies:
The security/cost of MODBUS is exceptionally inviting for most applications. It is a...
You could also look through the California Smart Grid initiatives, as they are trying to define...
Thank you all for your responses. I am strongly considering Modbus, because DNP3 seems to be...
Hi. You must pay attention in the security (cryptography) issues. A large scale data network...
Topic: Software, including programming, OS issues, etc.
from the Student advice department...
General Questions about MODBUS
Originally posted by Sandra on 29 September, 2014 - 8:12 am
A few questions about MODBUS protocol
New Replies:
> 1. Can Modbus create data groups/classes? Sometimes yes. > 2. Are the data types fixed,...
Topic: Communications systems and equipment.
from the Solar department...
Modbus Training Courses
Originally posted by Kyle on 19 December, 2013 - 9:37 pm
Looking for Modbus training courses
New Replies:
Texas Automation Systems which partners with Techstar gives great instruction on Modbus. ...
Topic: Communications systems and equipment.
from the Forum department...
MODBUS Break Condition & Checksum
Originally posted by Derek on 16 April, 2014 - 12:14 pm
MODBUS RTU using RS485 to RS232 converter connected to RS232 to USB converter to communicate with electric meter using MODBUS Poll.
New Replies:
I agree that the fewer converters you have transferring the signal, the better. Connecting one...
Topic: Communications systems and equipment.
from the Engineering design department...
RS485 Connnection to DV-6 VE4006P2
Originally posted by Bhaskar Mittal on 26 September, 2014 - 12:53 pm
Connecting DCS to VFDs on 485 Modbus RTU
New Replies:
Modbus is not plug-and-play even if Emerson's laughable marketing spiel, "Plug your Serial...
Topic: Software, including programming, OS issues, etc.
from the R & D department...
Enable Register Read in LabView
Posted by Ajay Waghmare on 20 September, 2014 - 3:44 am
When reading registers in MODBUS using LabViewm, how do I read data from registers at addresses 43XXX?
Posted by Beavis Cleavis on 19 September, 2014 - 1:07 pm
Bus contains isolated and non-isolated slaves. Considerations when connecting everything together?
Topic: Continuous process industries, DCS questions.
from the Forum department...
WDFP QLC Card Download
Posted by Kevin Williams on 18 September, 2014 - 12:27 pm
Problem downloading to QLC card with LC Loader
Topic: Communications systems and equipment.
from the ModbusTCP department...
PROSOFT MVI56-MNET Slave Response Time
Posted by Cris on 17 September, 2014 - 2:27 pm
PROSOFT MVI56-MNET communication response time and performance
Topic: Sensor technologies.
from the seeking product recommendations department...
Modbus TCP temperature monitor
Originally posted by mooseo on 28 February, 2011 - 2:09 am
I'm looking for a product recommendation
New Replies:
I am looking for much the same thing, a simple temp and humidity for my server room. I just want...
Topic: Software, including programming, OS issues, etc.
from the Modbus RTU Slave Simulation department...
Modbus RTU 2 slaves simulator
Originally posted by Vlad S. on 5 September, 2014 - 4:02 pm
How to simulate two Modbus RTU Slaves
New Replies:
ModMultiSim (see http://wingpath.co.uk/modbus/modmultisim.php) can simultaneously simulate two (or...
I have a generic inhouse Modslave.EXE application that responds to any Modbus Slave address it...
Topic: Communications systems and equipment.
from the Specification department...
Redundancy of Byte Count and Quantity
Posted by Jay on 9 September, 2014 - 4:49 am
Is there a need for both fields "Byte Count" _and_ "Quantity"?
Topic: Communications systems and equipment.
from the Forum department...
Dixell XC645 MODBUS Register
Posted by Bare on 3 September, 2014 - 3:41 am
Looking for information about MODBUS to connect to the registers in a Dixell XC645CX regulator
Topic: Local and wide area networking in factory automation.
from the Forum department...
TCP/IP over Ethernet
Originally posted by Tarun on 25 August, 2014 - 1:23 pm
Is TCP/IP on ethernet better?
New Replies:
> What does Ethernet port with web server mean? It means that the Ethernet port supports HTML...
Topic: Communications systems and equipment.
from the Instrument department...
ALE111 module send failure
Originally posted by Shahzad on 28 September, 2010 - 5:17 pm
Yokogawa ALE111 module communication problem
New Replies:
I have a similar problem. We are using ALE111 Ethernet card with controller ADV10D to communicate...
Topic: Local and wide area networking in factory automation.
from the Forum department...
MODBUS to Lan Convertor
Originally posted by danaqu on 26 August, 2014 - 2:53 pm
Looking for a MODBUS to Lan convertor.
New Replies:
Yes, for 150 meters you could even use spare cat5 pairs with rs485. Regards cww...
It might work. I didn't see any software for configuring it. That type of serial server is...
You may or may not need another converter at the PLC. I would get a pair of RS232 to RS485...
Topic: Computers in manufacturing; also hardware discussion.
from the Control department...
Profibus to Modbus
Originally posted by don on 4 September, 2012 - 9:31 am
Profibus (master)to modbus device on siemens txp
New Replies:
May I get details Please? I have Teleperm XP and want to talk to third party device using Modbus...
Originally posted by Harvard on 15 August, 2014 - 1:17 pm
Need to know how a slave device that lacks access to the RS-485 COMMON manage to maintain a Receiver common mode voltage between -7 and +12.
New Replies:
Many times 2 wire devices are referenced to frame ground and do not supply a terminal with + and -....
By Lynn August Linse on 18 August, 2014 - 10:17 am -
I guess one work around would be - if you have the common wire available in the bus cable - is use...
Thank you for the responses and no this is not a trick question. I am dealing with a...
Common mode voltage can be construed as the average of the differential signals, the more apt...
Topic: Communications systems and equipment.
from the Forum department...
Modbus Register Address
Originally posted by Whitepage on 15 August, 2014 - 4:30 am
I have a question about entering the register address in our program PME when I have a 4-digit address.
New Replies:
Actually, the original modicon only supported 0-999 addressing. Anyways, if your driver only...
If you are attempting to pair a master that won't allow configuration of offsets >9999 to a...
Dear Fred , Thanks for your advice. But now i don't know what i have to do for this...
Dear Darrin, Thanks for your reply Can you help to show me the way i can change the modbus...
Greetings, the short and quick answer is nothing. The first number in a Modbus register...
Topic: Sensor technologies.
from the Need to find a sensor department...
Lightning Sensor
Posted by Andrew on 19 August, 2014 - 7:18 pm
I'm trying to find a lightning sensor
Posted by ioudas on 19 August, 2014 - 1:16 pm
Trying to connect a bm85 to a 984 265. Via MODBUS+
Originally posted by ASCF on 4 March, 2014 - 4:08 am
I try to connect a Power Circuit breaker from Schneider to a Siemens PLC using Modbus RTU protocol.
New Replies:
Hi! Do you have some solution on your problem. I see we have the same HW and the same problem,...
Topic: Communications systems and equipment.
from the Automation List department...
Re: Replace RS-485 with Siemens Profibus Cable
Originally posted by Curt Wuollet on 14 August, 2014 - 9:15 pm
I am building a Modbus RTU network and am considering replacing RS-485 cable with Siemens Profibus cable. Want to hear from those who have done this.
New Replies:
Thanks Curt. I appreciate your answering. I donīt really mind about the purple color. :) Jimmy...

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