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SCXI-1322 Installation Guide
4
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It is important to notice that because the SCXI-1122 provides a single
voltage excitation channel, you can remotely sense your excitation voltage
at a single load location. Therefore, when using multiple loads, you either
have to sense in the terminal block (leave R3 and R4 in place) or make sure
your loads are located close to each other and remotely sense at the end of
the excitation leads. Use a single pair of excitation leads for all the loads,
as shown in Figure 1.
Figure 1.
Remote Sensing with Multiple Loads
Figure 2 shows a setup where remote sensing is not used. In this case, use
a different pair of excitation leads for each load. To minimize the voltage
drop in each pair of excitation leads, use large gauge wires to reduce the
I * R
LEAD
drop.
Figure 2.
No Remote Sensing
VEX +
CH+(0)
120
120
120
120
SENSE +
Use short lengths of large-gauge
wire to minimize the voltage
drop in each lead.
VEX –
SENSE –
Ω
Ω
Ω
Ω
120
120
Ω
Ω
CH+(1)
CH+(15)
VEX +
120
VEX –
120
120
120
120
120
I =
3.333 V
240+ 2R
LEAD
R
LEAD
Ω
Ω
Ω
Ω
Ω
Ω
CH+(0)
CH+(1)
CH+(15)
I
2R
LEAD
<< 240
Ω
Summary of Contents for SCXI-1322
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