54
CoriolisMaster FCB400, FCH400
CORIOLIS MASS FLOWMETER | OI/FCB400/FCH400-EN REV. E
… 7 Electrical connections
… Pin assignment
Digital output 41 / 42, 51 / 52 passive on distributed
control system
G12366
A
Ex.1
Ex.2
0 V DC
16 ... 30 V DC
B
Rx
Rx
41+
51+
I
E
42-/
52-
Ri
A
Transmitter
B
Distributed control system /
Memory programmable controller
Ex. 1 Input 1
Ex. 2 Input 2
R
X
Resistor for current limitation
R
I
Distributed control system
internal resistance
Figure 44: Digital output 41 / 42 on distributed control system (example)
The R
X
resistors limit the maximum current through the
optoelectronic coupler of the digital outputs in the transmitter.
The maximum permissible current is 25 mA. An R
X
value of
1000
Ω
/ 1 W is recommended at a voltage level of 24 V DC.
The input on the distributed control system is reduced from
24 V DC to 0 V DC (falling edge) with ‘1’ at the digital output.
Active current output V3 / V4
When the ‘loop power supply 24 V DC, blue’ plug-in card is used,
the current output on the plug-in card can also be wired as the
active current output.
G11742-01
A
V2-
V1+
I
E
+24 V
, max. 25 mA
DC
0V
4 ... 20 mA
V3+
V4-
B
OC1
OC2
R
B
A
‘Loop power supply (blue)’ plug-in card in slot 1
B
‘Passive current output (red)’ plug-in card in slot 2
Figure 45: Active current output V3 / V4 (example)
Digital input V3 / V4 active
When the ‘loop power supply 24 V DC, blue’ plug-in card is used,
the current output on the plug-in card can also be wired as the
active current output.
G11914
A
V2-
V1+
I
E
+24 V
, max. 25 mA
DC
0V
B
V4-
V3+
OC2
OC1
A
‘Loop power supply (blue)’ plug-in card in slot 1
B
‘Passive digital input (yellow)’ plug-in card in slot 2
Figure 46: Active digital output V3 / V4 (example)
