Baker Hughes Masoneilan SVI II AP Series, Быстрый старт

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= Masoneilan SVI II AP Digital Positioner Quick Start Guide | 112
Distributed Control Systems Configurations
This section gives guidance for configuration in a DCS
application. Figure
36 gives two generalized drawings that
cover DCS applications to ensure switch safety.
Figure 36 DCS Switches Wiring Options
Configuration Considerations
A typical value for 24 AWG cable about 0.025 Ohm/ft
(see Wiring Option #1)).
If IS barrier is a combination of fuse, resistor and Zener
diode then the connection is shown in Option #2. The
barrier must have adequate resistance to limit inrush
current, as the fuse cannot limit inrush current (see
Wiring Option #2).
Power source can be part
of DCS/PLS card. Power
source requirements: V

30 V. I
max

1 A.
SVI
Switch
Add resistor so load with
resistance ≥ 30 (including
wire resistance)
+
-
Negative switch pole must be directly wired to negative
+
-
Wiring Option #1
SVI
Switch
Add resistance sized to
limit in-rush current < 50
mA.
+
-
+
-
Wiring Option #2
Power source can be part
of DCS/PLS card. Power
source requirements: V

30 V. I
max

1 A.
Any load. Power source is not directly
connected to the switch.
Load can be a circuit within DCS/PLS
card, between power source and
switch.