Endress+Hauser Tankvision Gauge Link NXA20, Руководство по эксплуатации

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Tankvision Gauge Link Operation
Hauser 33
Example 8
A system requires to be connected to 4 of SAAB rosemount gauges address 01 - 04
Level only is required.
Host baud rate is 9600, with a parity of none.
7.1.10 Configuring through the Modbus Map
The holding registers which contain the gauge addresses etc can also be configured through
the RS485 Modbus host port using function code 3 of the Modbus protocol. Writing into
these registers is done using function code 6 or 16.
The purpose of this feature allows gauges to be added or deleted from a system remotely,
which allows host packages which have a configuration tool as part of it’s software suit to do
the configuration. This feature also allows its configuration to be stored remotely and the
configuration to be downloaded to the Tankvision Gauge Link on power up of a whole system
if required.
Refer to the Tankvision Gauge Link Modbus Map document for configuring the Tankvision
Gauge Link through the Modbus interface. The same principles apply when configuration is
done through the terminal emulation program, such as the gauges much be configured in
consecutive order (
→
ä
24).
The address when configuring the Tankvision Gauge Link is default 247 or any of the
addresses configured in holding registers 0 -31.
The only parameters which can not be configured through the modbus link are parameters,
such as the engineering mode, field mode, baud rates, parity, GPU gain.
7.2 Operation
The operation of the Tankvision Gauge Link is straight forward, the Modbus interface
complies with the Modbus specification. Refer to the document Tankvision Gauge Link
Modbus Map. In general data from each gauge and auxiliary device is mapped to an address
which is assigned in holding registers 0 – 31. The data will be picked up from the input
registers using function code 4. The Tankvision Gauge Link can support up to 32 Modbus
addresses, so in theory 32 gauges and auxiliary devices can be connected, but in practice the
electrical limitations of the BPM and TRL/2 field bus wouldn’t allow for this.
The Tankvision Gauge Link supports a range of different units, which are detailed in the
Tankvision Gauge Link Modbus Map. The Tankvision Gauge Link reads the units on power
Enter Result
HTS=9600(return)
HPA=N(return)
CONFIG(return) Enable configuration
0=1(return) Level address = 1 (modbus address = 1)
1=2(return) Level address = 2 (modbus address = 2)
2=3(return) Level address = 3 (modbus address = 3)
3=4(return) Level address = 4 (modbus address = 4)
(return)