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PBD-51041066
SITRANS LG270 - Operating Instructions
44295-EN-140321
5.5
Supplementary electronics
You can use the supplementary electronics - additional current output
to provided a second measured value.
Both current outputs are passive and need a power supply.
1
2
+
( )
(-)
I
4...20mA
I I
4...20mA
7
8
+
( )
(-)
3
1
2
Fig. 21: Connection compartment double chamber housing, supplementary
electronics - additional current output
1 First current output (I) - Voltage supply and signal output (HART)
2 Second current output (II) - Voltage supply and signal output (without HART)
3 Ground terminal for connection of the cable screen
5.6
Switch-on phase
After SITRANS LG270 is connected to the bus system, the instrument
carries out a self-test for approx. 30 seconds. The following steps are
carried out:
•
Internal check of the electronics
•
Indication of the instrument type, hardware and software version,
measurement loop name on the display or PC
•
Indication of the status message "
F 105 Determine measured
value
" on the display or PC
•
Status byte goes briefly to fault value
As soon as a plausible measured value is found, it is outputted to the
signal cable. The value corresponds to the actual level as well as the
settings already carried out, e.g. factory settings.
Supplementary electron-
ics - Additional current
output
