GE BAKER HUGHES Masoneilan SVi 1000 Quick Start Manual page 61

Distributed Control Systems Configurations
This section gives guidance for configuration in a DCS application. Figure 34 gives two general-
ized drawings that cover DCS applications to ensure switch safety.
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SVI
Switch
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SVI
Switch
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Configuration Considerations
© 2019 Baker Hughes, a GE company, LLC. All rights reserved.
Wiring Option #1
Add resistor so load with
resistance ≥ 30 (including
wire resistance)
Negative switch pole must be directly wired to negative pole of power supply.
Wiring Option #2
Add resistance sized to
limit in-rush current < 50
mA.
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.
Figure 34 DCS Switches Wiring Options
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
1 A.
Power source can be part
of DCS/PLS card. Power
source requirements: V 
30 V. I
max
Masoneilan SVi1000 Positioner Quick Start Guide =| 61
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max
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1 A.