National Instruments SCXI-1303, Руководство по установке

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© National Instruments Corporation 7 SCXI-1303 Installation Guide
Warning Connecting an external ground-referenced signal with the 10
Ω
bias resistor
network in place may cause permanent damage to the resistor network and the
traces on the SCXI-1303 printed circuit board. National Instruments is
NOT
liable
for any damage or injuries resulting from improper signal connections.
Signal Connection
When connecting your signals to the SCXI-1303, follow the labeling on the
SCXI-1303 for the appropriate module, as indicated in Figure 4.
To connect the signal to the terminal block, perform the following steps,
referring to Figures 3 and 4 as necessary:
1. Unscrew the top cover screws and remove the cover.
2. Loosen the strain-relief screws and remove the strain-relief bar.
3. Run the signal wires through the strain-relief opening. You can add
insulation or padding if necessary.
4. Prepare your signal wire by stripping the insulation no more than
7 mm.
Table 2. Selecting the Appropriate Resistor Networks
Module Bias Resistor
Pullup
Resistor
Source
Impedance
Signal
(Floating or
Ground-
referenced)
Open
Thermocouple
Detection? Comments
SCXI-1102
/B/C 10 M
Ω
10 M
Ω
Low Both Yes Recommended
configuration for the
SCXI-1102/B/C
10
Ω
10 M
Ω
Low Floating Yes Factory-shipping
configuration
10
Ω
None High or low Floating No —
None None High or low Ground-
referenced No —
SCXI-1100 10 M
Ω
10 M
Ω
— — — Not recommended
10
Ω
10 M
Ω
Low Floating Yes Factory-shipping
configuration
10
Ω
None High or low Floating No —
None None High or low Ground-
referenced No —
low source impedance
≤
50
Ω
high source impedance >50
Ω