Promotic
WikipediaLinkedInYoutubeTwitterFacebook

Communication with Landis&Gyr regulators

According to the method of the communication we divide Landis&Gyr regulators into two groups:
1. Landis&Gyr of the PRV1 and PRV2 types - communication by the PmChar driver.
2. Landis&Gyr of the PRU1, PRU2 and RWP types - communication by the internal Landis&Gyr protocol.
 
Both types of the communication have the following in common:

The Landis&Gyr regulators are not addressable, it goes about the point-to-point communication type. But it is possible to place a special external converter prior to each Landis&Gyr that provides addressing and the conversion of the line to the RS485 network communication.

The communication is implemented over the programming PG port. Data in the Landis&Gyr have no fixed address and even on the relatively small change of the program in the Landis&Gyr, addresses of variables in the Landis&Gyr are changed. Communication messages that write into the Landis&Gyr, can then cause the crash of the program in the Landis&Gyr when even tiny changes in the Landis&Gyr addresses layout are not accepted. This destruction can be non-reversible !! and even the reset of the Landis&Gyr won't help !! Thus it is important to know the exact address layout in the Landis&Gyr.

 

Communication by OPC server by the MC Control company

OPC server from this company is communication driver for devices Landis&Gyr of the type UNIGYR–RWP80 and PRU2 10.64b. Regulators can be connected by means of serial link RS232 or Ethernet. OPC server installer is available pn pages www.mccontrol.cz. OPC server is protected by HW key. Without HW key is server limited for one station for one hour.
 
Data transfer via RS232 interface:

Data transfer RS232 enables connecteng max one station RWP80 connected to serial port. Connecting other station requires new communication port.

 
Data transer via Ethernet:

The station is connected through communication converter Ethernet/RS-232. It is possible to connect more station to one TCP port, address is determined by IP address in network.

 
Trade terms:
- OPC server (Producer: MC Control s.r.o, Doubravice nad Svitavou, Czech republic, www.mccontrol.cz, info@mccontrol.cz).
- Using the OPC server is bound to purchase the PmOpcClient license. With the freeware version PmFree, or when developing the application (with development environment for tersting purposes), this component is always functional.

Communication by OPC server for PROFIBUS

It is possible to insert the PROFIBUS communication card into the controler of the PRU type. By such controller it is possible to communicate, for example, by the OPC server from Siemens company.

Communication with PRV1 and PRV2 regulators

The communication with the Landis&Gyr regulators of the PRV1 and PRV2 types is carried out in the PROMOTIC system by means of the PmChar communication driver. For the network communication (over the RS485) it is necessary to equip each Landis&Gyr station by the addressable HW converter.

 
Point-to-point communication:

The Landis&Gyr regulator can be programmed as the communication Slave (i.e. it waits for communication prompts=messages from the PC). This is the most often and recommended case how to implement the communication of an application with the Landis&Gyr stations. The Landis&Gyr regulator can be programmed as the Master as well (it transmits data to the communication line itself); or it can go about the combination of both approaches.

As a demonstration of the point-to-point communication example is available, where the PC is of the Master type and the Landis&Gyr station is of the Slave type. See: Example of communication with Landis&Gyr devices of PRV1/2 type. Example is implemented by the PmChar communication driver.

 
Network communication:

The communication with the Landis&Gyr stations of the PRV1 and PRV2 types can be driven on the RS485 line by intelligent HW converters that provide:

- addressing of the Landis&Gyr regulators.
- security of the Landis&Gyr protocol by the check sum.
- conversion of the RS232 signal to the RS485 - it enables to link up up to 32 Landis&Gyr regulators to one RS485 communication line.

Communication with PRU1/PRU2/RWP regulators by means of DLL library

The communication with the Landis&Gyr regulators of the PRU1, PRU2 and RWP types is implemented over the RS485 industrial network interface by the addressable HW converter and the SW communication driver (DLL library) as follows:

1. On the Landis&Gyr station side the communication is carried out over the PG port (RS232). Prior to each Landis&Gyr station the intelligent HW converter must be located. The HW converter performs:

- additional addressing the Landis&Gyr stations.
- it ensures communication messages by the check sum.
- it periodically provides current data from the Landis&Gyr station for requests from the PC.

2. On the PC side there is available the communication driver (DLL library). The PROMOTIC system accesses the DLL library by the PmDll object and calls its functions (data reading, data writing, etc.). The communication driver keeps the internal database of variables. This provides quick answers to PROMOTIC system requests because it doesn't wait for reading the real value from the Landis&Gyr but the value read from the internal database is returned. For the RS232/RS485 conversion a suitable external HW converter or a HW card into the PC can be used. On using the HW communication card in the PC the condition of the functionality is the correct detection of the HW card in the OS Windows (showing new COM ports in the OS Windows settings).

See: Example of communication with Landis&Gyr devices of RWP type.

 
Trade terms:
- The DLL library and the intelligent HW converter (Producer: CODEA s.r.o., Ostrava, Czech republic)
- Using the DLL library is bound to purchase the PmDLL license. With the freeware version PmFree, or when developing the application (with development environment for tersting purposes), this component is always functional.
© MICROSYS, spol. s r. o.Tavičská 845/21 703 00 Ostrava-Vítkovice