Burkert Type 8056 - Manual (Page 103)

- 103 - RS232_485_ETP_MODBUS_BU_REV02.doc
ATTENTION: when connecting to a modem, this latter must be configured because it only works autonomously
with data lines (without control lines RTS/DTR/CTS/DSR etc.). For this type of configuration, refer
to the modem manual.
NECESSARY PARAMETERS:
• Menu «7-Communication», function - «Speed 2»: set this value to the same speed as the PC or
modem. The speed may be chosen from 2400, 9600, 19200 and 38400 bps.
• Menu «7-Communication», function - «Print»: set to «OFF».
• The meter will communicate with ETP protocol as descript ahead.
• The aux modules supply the RS232 port to the meter.
• The command, formatted with ETP protocol, and send to RS232 of the aux module, for example through a
PC, are received by the meter that re-transmit the data, toward the door RS485, to the RS485 devices
connected. In the same way, the ETP commands received on the RS485 are re-transmitted to the RS232 port
connected to the PC.
• This is a typical case of a typical connection between a GSM modem and a local RS485 network of meters.
• Every command send to the meter and every returned response have two address: the "[address_to]"
(address of destination) and the "[address_from]" (address of origin).
• For examples for to send packets from a PC connected to the RS232 of the meter to the standard door RS485
of the meter, it is necessary that the address "[address_to]" (address of destination) must be the address of
the device connected on port RS4485 that is the device destination of the command.
• This address must be different from the meter address (Address on Menu «7-Communication»).
• This address must be also different from the value "232". The value 232 is not valid for this configuration.
• In this way each packet received on the door RS232 will be re-launched on the door RS485 toward the
connected meter.
• Besides, for make so that the deriving answer from this could reach the questioning device on the door
RS232, it is necessary that the address "[address_from]" (address of origin) will be set to the value" 232."
• In this way the data transit between a door and the other between the two connected devices. The meter
that stays in the half has only the function of receive and sort the packets of data between a door and the
other.
6.2. RS485 SERIAL PORT
Networks are used when there is a need to connect several instruments together. The interface usually used for this
type of connection is the RS485. There are various ways to make several instruments communicate in a network; the
way adopted in the Millennium series instrumentation is the MASTER-SLAVE type.
Up to 32 devices can be connected with this interface in a single network covering a length of up to 1200 metres with
only two wires. It has excellent immunity to electrical disturbance and is therefore used extensively in industry.
6.2.1. CONNECTING THE CONVERTER VIA RS485 SERIAL PORT
The RS485 port is suitable for even long distance and network connections because it is galvanically insulated from all
the rest of the appliance except for the RS232 port (if installed), with which it shares the power supply.
PARAMETERS:
• Menu «7-Communication», function -«Address»: set this value so that each instrument in the network has
a different address. The addresses possible go from 0 to 255., exclude 232, reserved to re-launched
between RS232 e la RS485.
• Menu «7-Communication», function - «Speed 1»: set this value to the same speed as the RS485 device
connected. The speed may be chosen from 2400, 9600, 19200 and 38400 bps.
•
See point 1.3 if you need to transmit data between RS 232 and RS 485