National Instruments VXI-SC-1102 Current-Loop Receivers

Chapter 2 Installation
© National Instruments Corporation 2-3 VXI-SC-1102/B/C User Manual
Current-Loop Receivers
The VXI-SC-1102/B/C submodules have pads for transforming
individual channels to current-to-voltage converters. National
Instruments offers an SCXI Process Current Resistor Kit of four 249 Ω,
0.1%, 5 ppm, 1/4 W resistors. The reference designators for the current
loop resistors have the following format: for input channel x, the
resistor is RCLx. For example, the resistor for channel 28 is RCL28.
Caution: Before installing the resistors in your submodule, make sure that there are
no signals connected to your submodule front connector.
Install the resistors by performing the following steps:
1. Follow the instructions in the VXI-SC-1000 Carrier Module
Installation Guide to remove your VXI-SC-1102/B/C submodule
from the carrier assembly.
2. Bend and trim the resistor lead as shown in Figure 2-2. Be sure that
the resistor does not extend more than 0.65 in. above the surface of
the circuit board.
Figure 2-2. Bent and Trimmed Resistor
3. Insert the resis tor into the ap propriate pad, labeled RC Lx.
4. Solder the leads to the pad on the bottom side of the module.
5. Follow the instructions in the VXI-SC-1000 Carrier Module
Installation Guide to replace the VXI-SC-1102/B/C submodule in
the carrier assembly.
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