National Instruments sbRIO-9218 User manual

GETTING STARTED GUIDE
sbRIO-9218
Non-Enclosed, 24-Bit, 51.2 kS/s/channel, 2-Channel C Series
Universal Analog Input Module
This document explains how to connect to the sbRIO-9218.
Note Before you begin, read the sbRIO-9218 Safety, Environmental, and
Regulatory Information document on ni.com/manuals and complete the software
and hardware installation procedures in your chassis documentation.
Note The guidelines in this document are specific to the sbRIO-9218. The other
components in the system might not meet the same safety ratings. Refer to the
documentation for each component in the system to determine the safety and EMC
ratings for the entire system.

sbRIO-9218 Pinout
V+ V–
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
2| ni.com | sbRIO-9218 Getting Started Guide

Table 1. Signals by Measurement Type
Mode Pin
1 2 3 4 5 6 7 8 9
±16 V EX+ — AI-,
EX- — — AI+ — — —
±65 mV EX+ 1— EX- 1— — AI+ AI-2— —
Full-
Bridge EX+ 1— EX- 1RS+ RS- AI+ AI- SC SC
IEPE — AI+ AI- — — — — — —
TEDS — T+ 3T- — — — — — —
Table 2. Signal Descriptions
Signal Description
AI+ Positive analog input signal connection
AI- Negative analog input signal connection
EX+ Positive sensor excitation connection
EX- Negative sensor excitation connection
1Optional sensor excitation.
2Tie to pin 3.
3TEDS Class 1 data connection.
sbRIO-9218 Getting Started Guide | © National Instruments Corporation | 3

Table 2. Signal Descriptions (Continued)
Signal Description
RS+ Positive remote sensing connection
RS- Negative remote sensing connection
SC Shunt calibration connection
T+ TEDS data connection
T- TEDS return connection
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sbRIO-9218 Block Diagram
CH0
Isolation
Isolation
Vsup
sbRIO-9218
Input
Connector
Power
Connector
External
Power Supply
Measurement Type
Signal Conditioning
12 V
Excitation
IsolatorADC
CH1
Input
Connector
Measurement Type
Signal Conditioning
12 V
Excitation
IsolatorADC
Hardware Components
Software-Selectable
Externally Supplied Voltage
Legend
Data
• Two 24-bit analog-to-digital converters (ADCs) simultaneously sample both AI
channels.
• The sbRIO-9218 provides channel-to-channel isolation.
• The sbRIO-9218 reconfigures the signal conditioning for each measurement type.
• The sbRIO-9218 provides excitation for IEPE and bridge completion measurement
types.
• The sbRIO-9218 can provide optional 12 V sensor excitation for ±16 V, ±65 mV, and
±20 mA measurement types.
sbRIO-9218 Getting Started Guide | © National Instruments Corporation | 5

±16 V and ±65 mV Signal Conditioning
AI+
AI- ADC
Amplifier
Overvoltage
Protection
Prefilter sbRIO-9218
Input signals on each channel are buffered, conditioned, and then sampled by an ADC.
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Full-Bridge Signal Conditioning
+ –
Reference
Input
AI+
EX+
RS+
AI–
EX–
RS–
SC
SC
sbRIO-9218
ADC
• The analog input connections sense then amplify the incoming analog signal.
• The excitation connections provide differential bridge-excitation voltage.
• Remote sensing continuously and automatically corrects for lead-wire induced
excitation voltage loss when using the RS connections.
• Shunt calibration can be used to correct for lead-wire induced desensitization of the
bridge.
sbRIO-9218 Getting Started Guide | © National Instruments Corporation | 7

IEPE Signal Conditioning
2 mA
IEPE
Amplifier
and
Prefilter
AC Coupling
sbRIO-9218
+
–
ADC
AI+
AI-
• The incoming analog signal is referenced to an isolated ground.
• Each channel is configured for AC coupling with an IEPE current.
• Each channel provides a TEDS Class 1 interface.
±20 mA Signal Conditioning
AI+
DSUB
AI- ADC
Amplifier
Overvoltage
Protection
Current
Shunt
Prefilter sbRIO-9218
The NI-9983 provides a current shunt for the incoming analog signal.
8| ni.com | sbRIO-9218 Getting Started Guide

±60 V Signal Conditioning
AI+
DSUB
AI- ADC
Amplifier
Overvoltage
Protection
Prefilter sbRIO-9218
The NI-9987 provides an attenuator for the incoming analog signal.
Half-Bridge Signal Conditioning
+ –
Reference
Input
sbRIO-9218
ADC
DSUB
AI+
EX+
RS+
EX–
RS–
SC
SC
• The NI-9886 provides half bridge completion resistors for the incoming analog signal.
• You must connect AI+, EX+, and EX-.
• RS+ and RS- connections are optional.
• You do not need to connect the AI- signal because it is connected internally.
sbRIO-9218 Getting Started Guide | © National Instruments Corporation | 9

Quarter-Bridge Mode Conditioning
+ –
Reference
Input
sbRIO-9218NI-9984/9985
ADC
DSUB
AI+
EXC
RC
The NI-9984 and NI-9985 provide a quarter-bridge completion resistor and half-bridge
completion resistors.
Measurement Types
The sbRIO-9218 provides built-in support for the following measurement types.
• ±16 V
• ±65 mV
• Full-Bridge
• IEPE
Tip NI recommends using the NI-9982 screw-terminal adapter when using built-
in measurement types on the sbRIO-9218.
The sbRIO-9218 provides additional support for the following measurement types when
using a measurement-specific adapter.
• ±20 mA, requires the NI-9983
• ±60 V, requires the NI-9987
10 | ni.com | sbRIO-9218 Getting Started Guide