Using the isolated loop supply of the scc-co20 – National Instruments Isolated Current Output Module SCC-CO20 User Manual

Page 4

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SCC-CO20 Isolated Current Output Module User Guide

4

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Figure 1. SCC-CO20 Signal Connections to E/M Series DAQ Device

Using the Isolated Loop Supply of the SCC-CO20

You can connect the SCC-CO20 to a load using either the isolated internal
loop supply or an external supply. The internal loop supply outputs a
voltage of 15 V with respect to the isolated ground reference. When using
the internal loop supply, the compliance voltage is 12.5 V. This allows for
a maximum load resistance of 625

Ω at 20 mA. Figure 2 shows how to

connect the SCC-CO20, using the internal loop supply, to a nonreferenced
(floating) load and to a load with a high common-mode voltage.

Figure 2. Connecting the SCC-CO20 Using the Internal Loop Supply

AO GND

E/M Series

DAQ Device

AO (X )

SCC-CO20

1

2

+

15 V iso

3

I

High
CMV

SCC-CO20

1

2

Load

+

15 V iso

3

0–20 mA

0–20 mA

SUPPLY

SINK

I

SCC-CO20

1

2

Load

+

15 V iso

3 SUPPLY

SINK

I

+

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