
26
5 Connecting to power supply and bus system
VEGABAR 83 • Modbus and Levelmaster protocol
46295-EN-131107
+
+
power supply
MODBUS
D0
D1
IS GN
D
USB
1
2
4
3
1
3 4 5
2
off on
( )
(
)
(-)
(-)
Fig. 22: Connection compartment
1 USB interface
2 Slide switch for integrated termination resistor (120 Ω)
3 Voltage supply
4 Modbus signal
Terminal
Function
Polarity
1
Voltage supply
+
2
Voltage supply
-
3
Modbus-Signal D0
+
4
Modbus-Signal D1
-
5
Function ground with installa-
tion according to CSA
5.5 Switch-on phase
After connecting the instrument to power supply or after a voltage
recurrence, the instrument carries out a self-check for approx. 10 s:
•
Internal check of the electronics
•
Indication of the instrument type, hardware and software version,
measurement loop name on the display or PC
•
Indication of a status message on the display or PC
•
The output signal jumps to the set fault current
Then the actual measured value is outputted to the signal cable. The
value takes already carried out settings, e.g. default setting into ac-
count.
Connection compartment