According to the method of the communication we divide
Landis&Gyr regulators into two groups:
1st
Landis&Gyr of the
PRV1 and
PRV2 types - communication by means of the
PmChar communication driver.
2nd 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.
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 will not help !! Thus it is important to know the
exact address layout in the
Landis&Gyr.
Communication by OPC server by the MC Control company
The 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 via the computer's serial port
RS232 or via Ethernet. OPC server installer is available on pages
http://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 allows connecting 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:
- The usage of the
PmaOpcDaClient object requires purchase of the
"PmOPC" licence. With the freeware version
PmFree, or when developing the application (with
development environment for testing 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 by the 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:
Preconfiguration "PmChar - Communication with Landis&Gyr regulators PRV1". 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 allows 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:
1st 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.
2nd On the
PC side there is available the
communication driver (DLL library). The PROMOTIC system accesses the DLL library by the
PmaDll 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).
Trade terms:
- The DLL library and the intelligent HW converter (The manufacturer: CODEA s.r.o., Ostrava, Czechia)
- The usage of the
PmaDll object requires purchase of the
"PmDLL" licence. With the freeware version
PmFree, or when developing the application (with
development environment for testing purposes), this component is always functional.