National Instruments 9213E User manual

OPERATING INSTRUCTIONS AND SPECIFICATIONS
NI 9213E
16-Channel Thermocouple Input Module

NI 9213E Operating Instructions and Specifications 2 ni.com
This document describes how to use the National Instruments 9213E
and includes dimensions, terminal assignments, and specifications for
the NI 9213E. Visit ni.com/info and enter rdsoftwareversion
to determine which software you need for the modules you are using.
For information about installing, configuring, and programming the
system, refer to the system documentation. Visit ni.com/info and
enter cseriesdoc for information about C Series documentation.
Caution National Instruments makes no electromagnetic
compatibility (EMC) or CE marking compliance claims
for the NI 9213E. The end-product supplier is responsible
for conformity to any and all compliance requirements.
Caution The NI 9213E must be installed inside a suitable
enclosure prior to use. Hazardous voltages may be present.

© National Instruments Corp. 3 NI 9213E Operating Instructions and Specifications
NI 9213E Dimensions
The following figure shows the dimensions of the NI 9213E.
Figure 1. NI 9213E Dimensions in Millimeters (Inches)
73.4 (2.89)
0.0 (0.00)
26.7 (1.05)
58.4 (2.30) 66.0 (2.60)
0.0 (0.00)

NI 9213E Operating Instructions and Specifications 4 ni.com
Connecting the NI 9213E
The NI 9213E has a 36-terminal detachable spring-terminal
connector that provides connections for 16 thermocouple channels.
Figure 2. NI 9213E Terminal Assignments
NC
TC0+
TC1+
TC2+
TC3+
TC4+
TC5+
TC6+
TC7+
TC8+
TC9+
TC10+
TC11+
TC12+
TC13+
TC14+
TC15+
COM
NC
TC0–
TC1–
TC2–
TC3–
TC4–
TC5–
TC6–
TC7–
TC8–
TC9–
TC10–
TC11–
TC12–
TC13–
TC14–
TC15–
COM
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36

© National Instruments Corp. 5 NI 9213E Operating Instructions and Specifications
You can connect thermocouple input signals to the NI 9213E.
Connect the positive lead of the thermocouple to the TC+ terminal
and the negative lead of the thermocouple to the TC– terminal. If
you are unsure which of the thermocouple leads is positive and
which is negative, check the thermocouple documentation or the
thermocouple wire spool.
The NI 9213E also has two common terminals, COM, that are
internally connected to the isolated ground reference of the
module. If you are using a shielded thermocouple, connect COM
to the shield and the shield to a common-mode voltage reference of
the thermocouple. A common-mode voltage reference is a voltage
that is within ±1.2 V of the common-mode voltage of the
thermocouple. If you are using a floating thermocouple or a
thermocouple within ±1.2 V of earth ground, connect COM and the
shield to earth ground. The shield grounding methodology can vary
depending on the application. Refer to Figure 3 for an illustration
of a typical shielding configuration.

NI 9213E Operating Instructions and Specifications 6 ni.com
Figure 3. Connecting a Shielded Thermocouple Input Signal to the NI 9213E
Thermocouple
TC–
COM
TC+
Shield
NI 9213E
Vreference

© National Instruments Corp. 7 NI 9213E Operating Instructions and Specifications
Connecting Wires to the NI 9213E Connector
Use a flathead screwdriver with a blade smaller than 2.3 × 1.0 mm
(0.09 × 0.04 in.) to connect wires to the detachable spring-terminal
connector. Insert the screwdriver into a spring clamp activation slot
and press a wire into the corresponding connector terminal, then
remove the screwdriver to clamp the wire into the terminal. Refer
to the Specifications section for more information about
spring-terminal wiring. Refer to Figure 4 for an illustration of
connecting wires to the NI 9213E.
Figure 4. Connecting Wires to the NI 9213E Connector

NI 9213E Operating Instructions and Specifications 8 ni.com
NI 9213E Circuitry
Each channel of the NI 9213E passes through a differential filter
and then is multiplexed and sampled by a 24-bit analog-to-digital
converter (ADC). Each channel also has an open thermocouple
detection (OTD) circuit, which consists of a current source
between the TC+and TC– terminals. If an open thermocouple is
connected to the channel, the current source forces a full-scale
voltage across the terminals. Refer to Figure 5 for an illustration of
the input circuitry for one channel of the NI 9213E.
The NI 9213E multiplexes 16 thermocouple input channels,
1 cold-junction compensation (CJC) channel, and 1 autozero
channel to a single ADC. Each channel has a resistor that produces
an input impedance between the TC+and COM terminals and
between the TC– and COM terminals. The gain and offset errors
resulting from the source impedance of connected thermocouples
are negligible for most applications. Thermocouples with a higher
lead resistance can introduce more significant errors. Refer to the
Specifications section for more information about errors resulting
from source impedance.

© National Instruments Corp. 9 NI 9213E Operating Instructions and Specifications
Figure 5. Input Circuitry for One Channel of the NI 9213E
The channels share a common ground, COM, that is isolated from
other modules in the system. The NI 9213E common-mode range
is the maximum voltage between any channel and COM. If COM
is not connected, then the common-mode voltage range is the
maximum voltage between any two channels. The NI 9213E
measures the common-mode voltage level of each channel and
returns a warning in the software if the signal is outside the
TC+
TC–
COM
NI 9213E
Input
Impedance
Open
Thermocouple
Detection
Current
Filtered
Differential
Amplifier
and
Multiplexer
Isolated
ADC
39 MΩ
39 MΩ

NI 9213E Operating Instructions and Specifications 10 ni.com
common-mode voltage range. Refer to the Specifications section
for more information about the common-mode voltage range.
The NI 9213E supports high-resolution and high-speed timing
modes. High-resolution timing mode optimizes accuracy and noise
and rejects power line frequencies. High-speed timing mode
optimizes sample rate and signal bandwidth. Refer to the
Specifications section for more information about the
high-resolution and high-speed timing modes. Refer to the
software help for information about setting the timing mode, or
conversion time, in software. Visit ni.com/info and enter
cseriesdoc for information about C Series documentation.
Temperature Measurement Accuracy
Considerations
Temperature measurement errors depend partly on the
thermocouple type, the accuracy of the thermocouple, the
temperature being measured, and the cold-junction temperature.
Refer to the Temperature Measurement Accuracy section in the
Specifications for the errors for each thermocouple type when
connected to the NI 9213E. The errors do not account for the
accuracy of the thermocouple itself.