ELECTRICAL CONNECTIONS
4
33
H250 M40
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03/2020 - 4000640706 - MA H250-M40 R06 en
Value range applies only when connected to a switching amplifier with the following
reference values:
•
Open-circuit voltage U
0
= 8.2 VDC
•
Internal resistance R
i
= 1 k
Ω
To ensure the value ranges, a load R
L
between 250
Ω
and 1 k
Ω
is recommended for the passive transistor
output with a nominal voltage of 24 VDC.
If other loads are used, caution is advised as the range of values of the signal voltages then no longer
corresponds to the range of values for the inputs of process control systems and controls (DIN IEC 946).
Figure 4-9: Connection switching output
1
NAMUR terminal connection
2
Isolated switching amplifier
3
OC switch output terminal connection
4
Power supply U
ext.
5
Load R
L
NC contact
NO contact
Switching value reached
< 1 mA
> 3 mA
Switching value not reached
> 3 mA
< 1 mA
Table 4-4: Value range for NAMUR
Signal voltages
U
L
[V]
U
H
[V]
lower limit
upper limit
lower limit
upper limit
via load R
L
0
2
16
30
Table 4-5: Value range for transistor output
Signal currents
I
L
[mA]
I
H
[mA]
lower limit
upper limit
lower limit
upper limit
Category 2
0
2
20
110
Table 4-6: Value range for transistor output
CAUTION!
The upper limit of the signal current must not be exceeded as this may damage the transistor
output.