Dräger Polytron 7000 Instructions For Use Manual page 19

— The cable resistances given apply for the maximum possible number of
transmitters as well as a load resistance of 250
can drastically reduce the maximum possible cable resistance!
The following tables show permissible combinations of transmitters, supply

voltages and maximum possible cable lengths.
— The capacitance values are typical values for commercially available
shielded cables with PVC insulation. The use of cables with different capac-
ity values will result in other cable lengths.
Transmitter Number of trans-
supply unit
Endress +
Hauser:
RN 221 N
MTL:
MTL 5042
Pepperl & Fuchs:
KFD2–STC4–Ex1
Stahl:
9160/13–11–11
Ω
0.5 mm
mitters
265 pF/m
1 1042 m
2 1007 m
3 972 m
4 936 m
5 901 m
6 702 m
1 463 m
2 463 m
3 463 m
4 463 m
5 463 m
6 379 m
7 281 m
1 1042 m
2 1007 m
3 972 m
4 936 m
5 901 m
6 140 m
1 1042 m
2 1007 m
3 972 m
4 936 m
5 901 m
6 865 m
7 281 m
. Higher load resistances
Maximum possible cable length
2 2
0.75 mm
320 pF/m
921 m
890 m
860 m
829 m
799 m
768 m
695 m
695 m
695 m
695 m
695 m
569 m
421 m
921 m
890 m
860 m
829 m
799 m
211 m
921 m
890 m
860 m
829 m
799 m
768 m
421 m
Electrical connections
2
1.5 mm 2.5 mm
375 pF/m 400 pF/m
828 m 792 m
801 m 766 m
774 m 740 m
747 m 714 m
720 m 689 m
693 m 663 m
828 m 792 m
801 m 766 m
774 m 740 m
747 m 714 m
720 m 689 m
693 m 663 m
666 m 637 m
828 m 792 m
801 m 766 m
774 m 740 m
747 m 714 m
720 m 689 m
421 m 663 m
828 m 792 m
801 m 766 m
774 m 740 m
747 m 714 m
720 m 689 m
693 m 663 m
666 m 637 m
2
19