Setting up a PROFINET I/O Connection

This topic describes the steps generally required to set up a PROFINET I/O connection with the RMC. For a step-by-step procedure for doing these steps on a Siemens S7 PLC, see the Using Siemens S7 PLCs via PROFINET topic. For details on controlling the RMC once a connection has been made, see the Using a PROFINET I/O Connection topic.

Setting up a PROFINET I/O connection requires steps in RMCTools and in the IO-Controller’s setup software (such as TIA Portal for Siemens S7 PLCs).

Cyclic and Acyclic Data

The PROFINET IO connection can be configured for both cyclic and acyclic I/O data. Understanding these methods of data transfer will help you determine how you wish to configure the PROFINET connection.

Cyclic I/O data is always sent between the PLC and RMC at the specified update time. For example, status information from the RMC, and variables to be written to the RMC would typically be part of the cyclic data. Cyclic I/O data is defined by the Incoming and Outgoing Cyclic I/O Data.

Acyclic data is sent only when it is needed. It is useful for infrequent data transfers, or for very large data transfers. For example, if the PLC creates a curve and sends it to the PLC, that data would typically be sent via the acyclic data. Or, if the PLC needs to read a captured plot from the RMC, that is also best done via the acyclic data. Acyclic I/O data is defined by the Data Records. The maximum length is 2048 registers (8192 bytes).

PROFINET Settings in RMCTools

Selecting PROFINET Protocol Mode (RMC200 Only)

In order to communicate via PROFINET I/O, the RMC200 must be set to PROFINET Mode:

In the Project pane, expand the RMC, and double-click the CPU.
On the Ethernet page, in the Ethernet Protocol Mode section, click PROFINET Mode, then click OK.

The Ethernet Protocol Mode may also be viewed on the RMC200 Display Screen.

Setting the PROFINET Device Name

The primary identifier for PROFINET nodes is the device name. To set the device name for the RMC using RMCTools, use the PROFINET Settings page.

Setting up the Outgoing and Incoming Cyclic I/O Data Areas

Each PROFINET I/O connection will cyclically transfer Input data and Output data at the specified update time. The location of the Outgoing Cyclic I/O Data, sent from the RMC to PLC, and the location where the Incoming Cyclic I/O Data sent from the PLC to the RMC is stored must be set in RMCTools using the PROFINET Settings page.

Notice that only the starting address for each data area is specified in RMCTools. The length of each data block is determined by which input and output module is selected in the IO-Controller’s PROFINET setup. See Selecting the Input and Output Modules below for details.

For almost all applications, the starting location for the Outgoing Cyclic I/O Data is left at its default of the start of the Indirect Data Map area. For most applications, the starting location for where the Incoming Cyclic I/O Data is stored is also left at its default location in a separate Indirect Data Map area, but the Variable Table and Command Area are also plausible destinations.

Selecting the Synchronization Method

The user has the option of including or not including a Sync Register at the beginning of the Incoming and Outgoing I/O Data. This option is selected in RMCTools on the PROFINET Settings page. For a description of the benefits of each method, see the Using a PROFINET I/O Connection topic.

Configuring Data Records

The configuration of Data Records does not need to be completed in order to establish a PROFINET I/O connection. Data Records apply to acyclic read and writes and are described fully in the Using PROFINET Record Data topic.

Setting the Byte Order

The RMC supports both Most Significant Byte (MSB) First and Least Significant Byte (LSB) First. The default is MSB First, which should be correct for most PROFINET controllers, including Siemens S7 PLCs.

Setting the IP Address from RMCTools

PROFINET supports setting the IP address from the PROFINET controller or configuration tool. However, it is recommended that RMCTools be used to set the IP address in order to ensure that the RMC is always accessible from RMCTools. To set the IP address for the RMC, use the RMC Ethernet Settings Page.

PROFINET Settings in the PROFINET Configuration Software

Once the PROFINET Device Name, Outgoing and Incoming Cyclic I/O Data areas, and Synchronization Method have been set in RMCTools, the rest of the PROFINET configuration is done in the PROFINET configuration software, which is specific to the IO-Controller being used. For Siemens S7 controllers, the Devices and Networks tool within Siemens TIA Portal is typically used.

Installing the GSD File

Before an RMC device can be added to the PROFINET configuration, the GSD files for the RMC must be installed in the PROFINET configuration software. The PROFINET GSD files for the RMC controllers are available for download from Delta’s website, and are installed in a PROFINET subfolder under the RMCTools install folder, for example C:\Program Files\RMCTools\PROFINET.

Delta provides GSDML files for each product:

GSDML-Vn.n-Delta-RMC75E-yyyymmdd.xml
GSDML-Vn.n-Delta-RMC150E-yyyymmdd.xml
GSDML-Vn.n-Delta-RMC200-yyyymmdd.xml

The most recent GSD versions are included with the RMCTools installation. Contact Delta for older versions if required for use with older PROFINET configuration software.

Notice that each of the RMCs has an associated image file. These should be the in same folder as the GSD file when it is installed into the PROFINET configuration software.

Selecting the Device Access Point (DAP)

After the GSD files have been installed into the PROFINET configuration software, the RMC can be added to the PROFINET network. This generally involves browsing through the device library to find the desired device and selecting the Device Access Point (DAP) to use:

RMC75E V1.0
RMC150E V1.0
RMC200 CPU20L V1.0
RMC200 CPU40 V1.0

To add the RMC to the PROFINET network, the user generally drags the desired DAP onto the PROFINET network.

Using the PROFINET Flash LED Feature

PROFINET allows the configuration software to flash an LED on a node to help identify which nodes correspond to which physical device:

RMC150E: the CPU LED will flash when instructed to do so by PROFINET.
RMC75E: the Controller LED will flash. Notice that the Controller LED will also flash when in PROGRAM mode. Therefore, you may need to set the RMC75E to RUN mode before verifying a device using the PROFINET flash LED feature.
RMC200: all LEDs on the CPU will flash in unison.

Setting the Device Name

Each IO-Device added to a PROFINET configuration must have a Device Name. Set the Device Name for the RMC in the PROFINET configuration software to match the Device Name set in RMCTools.

Notice that many PROFINET configuration software packages can also set the Device Name, which the RMC does support. However, it is generally easiest to set it directly in RMCTools so that the Device Name can also be saved in the RMCTools project file.

Setting the IP Address

PROFINET allows several methods of allocating the IP address in IO-Devices. The traditional method is to set the IP address for the IO-Devices when configuring the PROFINET network, and then the IO-Controller will find the IO-Devices by device name and configure the IP addresses as part of connecting to them. This method is not recommended because it can result in the IP address being changed or cleared at times when RMCTools is connected to the RMC.

An alternative method is to set the IP address settings in RMCTools, and then instruct the IO-Controller through the PROFINET Configuration Software to leave the IP address as it is when connecting to the IO-Device. For example, Siemens TIA Portal V14 includes an IP address is set directly at the device checkbox in the IO device’s Ethernet Addresses properties that should be checked to choose this option. This is the recommended method for RMC controllers.

Selecting the Input and Output Modules

The RMC PROFINET devices are set up to have 3 virtual slots. The first slot is the DAP, and will be named RMC150E, RMC75E, RMC200 CPU20L, or RMC200 CPU40. The second slot is the Input Slot, and the third slot is the Output Slot. In the PROFINET IO device library, under the selected DAP, you will find a folder of input modules and a folder of output modules. Select exactly one Input module and one Output module to install in slots 1 and 2 respectively.

The Input and Output modules to choose from differ only in the number of registers to be transferred. The Input module corresponds to the Outgoing Cyclic I/O Data area in the RMC, and the Output module corresponds to the Incoming Cyclic I/O Data area. Notice that if the Sync Register is used, the first register in each block will be reserved as the Sync Register.

Setting the Update Time

One additional item configured in the PROFINET configuration software that affects the PROFINET communication with the RMC is the Update Time. The RMC75E and RMC150E controllers support update times of 2, 4, 8, 16, 32, 64, 128, 256, and 512 ms. The RMC200 supports these same update times, plus 1 ms. Notice that the update time cannot be set lower than the Loop Time of the RMC. Therefore, if a 4 ms loop time is used, then the minimum PROFINET update time will be 4 ms. A typical update time is 16 msec. Choosing a faster update time than necessary may use excessive Ethernet bandwidth.

Related to the Update Time is the Watchdog Time. This is specified as a multiple of the Update Time. For example, with a Watchdog Time multiplier of 3 and an Update Time of 16 ms, the Watchdog Time will be 48 ms. Most IO controllers fix this value at 3, but some may allow configuration of this value.