Serial Interface/Modem; Rs 422/Rs; Profibus Dp; Setting Up A Modem Link - Endress+Hauser memo-graph Version II Betriebsanleitung

7. Serial interfaces/Modem
7.1 RS 232

7.2 RS 422/RS 485

7.3 PROFIBUS DP

7.4 Setting up a modem
link
Modem at the unit
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7. Serial interface/modem

The RS 232 serial interface can be found at the front of the unit (3.5 mm stereo socket
under the diskette drive) as well as on the rear of the unit (9 pin Sub D socket).
Attention: Simultaneous use of the front and rear RS232 interfaces is not permitted.
Unit will malfunction!
These interfaces can be found as an alternative on the unit rear panel.
RS 422 and RS 485 can be used for remote setting up/read out of data (up to approx.
1000 m cable length). Please make sure that when using an RS 232/RS 485 convertor
this supports automatic switching between transmitting and receiving (e.g. W+T type
86000).
When connected to PROFIBUS DP measured values can be displayed, recorded and
monitored. These measurement points are treated in the same way as conventionally
wired analogue signals.
Both PROFIBUS and conventionally connected signals can be used simultaneously
on one unit. This is due to the fact that the input signal for each channel can be
separately selected. Up to a total of 16 measurement points (with the additional
digital and mathematics channels) are available per unit.
The RS 485 interface is physically used for this (Baud rate 93.750 kBit/s, alternatively
45.45 kBaud, these are fixed).
A selection between the operation modes "Monitor" and "Master" (see "Set-up -
Sundries - PROFIBUS DP") can be made.
Operation mode „Monitor":
A Master (e.g. available computer system) interrogates the connected slaves without
influencing the system.
The measured data of the slaves is analysed. For this the setting of the slave address
and data format for each channel is required (see "Set up - analogue inputs - channel
xx - PROFIBUS DP"). The transmitter specification/settings must be noted.
Should a slave deliver more than one measurement (multi parameter transmitter)
each measurement requires its own input channel.
Hints:
• In order to be correctly displayed the real physical measured values (e.g. in C,
bar...) must be transmitted. Scaling on the unit is not possible.
• Please make sure that connections not needed in the plug are not connected.
• PROFIBUS PA can be used via a PA/DP bus coupler ("Segment coupler").
• PROFIBUS measurement points can be combined with each other and with
conventionally connected analogue signals by using the mathematics module.
Basically every normal commercial modem using AT commands can be used in order
to transmit data between the VDM RS 232 interface and the delivered PC software.
The modem that is to be used at the VDM end of the link must first be initialised using
the PC software (Miscellaneous - Set up modem for connection to unit).
In order to do this the modem is first connected to the PC using the modem original
connection cable (is normally delivered with the modem)
The initialisation must be done using the identical data format (Baurate, Data bits,
Parity) as in the VDM unit.