Delta Industrial Automation

Tips & Tricks


Distributed I-O

Successful Application – Profibus communication with VFD-EL & CME-PD01

It’s well known that Profibus is quite extended within industrial enviroment.
But this doesn’t mean that you need to use Siemens inverter when the fieldbus network is already setup!

We know that Simatic Step7 is not a piece of cake…
So, on the tutorial below you will find step by step, how to manage Simatic Step7 to be able to add Delta Inverter VFD-EL (with Profibus card CMA-PD01) into some profibus network.

Probably you will need GDS file.

And the tutorial
Delta – Siemens comunication VFD-EL via CME-PD01 (Profibus)

Let us know If this information is important for you, and we’ll post the same for new inverters like C2000 or CP200.
Ah! and remeber our profibus slave module in case you need to add cost effective remote I/O

PLC-Link (PLC to PLC)

I have been a long time that I would like to post this post.

PLC-Link is a Delta protocol to share easily memory area between 2 PLC’s.
Basically, the big advantage of PLC-Link is to work with Delta PLC’s as Remote I/O units.

Furthermore, you can use Delta PLC as Remote I/O or any other Delta device (Servodrive, Inverter, etc..) because the protocol used to share the info is Modbus.
Today we’ll focus on how to communicate one PLC master with 2 PLC slaves.

Network Structure:

The communication will be Modbus RS485, so the wiring is so simple, two twisted pairs from connector to connector.

We decide to use 9600, 7, E, 1, ASCII, but you can use higher baudrate. In fact the new S2 PLC series (SS2, SX2, SA2, ES2 and EX2) can reach 921Kbps!!

Memory Mapping:
The plan is to share 6 registers from the slave 1 and put it inside the memory of the master.
And on the other way around too, put 6 registers of the master on the memory of the Slave one.

See below table

As you could see on the Slave software we transform the first three shared words to Slave Inputs and Outputs.
This is the proper way to read remotely the I/O of the slave into the master.


Program Master
Program Slave 1
Program Slave 2

Alternate mirror all together
name: den-eindhoven
Password: BuPd2175

Remember to enable PLC-link on network 5 to start to share.
And if some trouble occurs just try to reset the communication with the RESET_Com Symbol.


Analog Control II (distributed Analog I/O)

The people who use to work with Delta analog I-O modules, use to have the same doubt.
Why the engineers put a RS485 port on analog I-O’s if you use internal bus to communicate with them?

The reason is very simple, our analog I-O’s can work trough the internal bus, but can work too trough RS485 communication too.
So, with that feature, is possible to create a remote analog I/O’s without any other device.
Just as a reminder, if you need to add digital I/O’s to your, then you should have to add the RTU-RS485 module to your distributed network.

The process to configurate the network is not difficult, but you have to go step by step.
1. The first step to configurate the RS485 protocol into the analog module, is runing the following example, who is ready to communicate with the PLC at ASCII 9600 7,E,1.
DVP04TC RS485 config communication.dvp
If you are interested to know how I did it, go to the Analog Control post

2. Once the protocol is configured, you can double check with the Extension Module Wizard and some IFD6500 (USB to RS485 converter) connected to our computer.

3. Finally, to work with them trough RS485, you just have to communicate with the analog module as an Inverter or temperature controller, or any other RS485 based device.
To Write
MODWR “Station Address” “CR number” “Number of data to be write”
To Read
MODRD “Station Address” “CR number” “Number of data to be read”
And SET/RST teh M1122 to trigger the command

Check the following example for better comprehension
DVP04TC RS485 Read-Write.dvp

name: den-eindhoven
Password: BuPd2175

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