Voltage Input Terminals (±V0H/V0L To ±V3H/V3L); Sensor Input Terminals (T0H/T0L To T3H/T3L) - Omega OM-USB-TEMP-AI User Manual

OM-USB-TEMP-AI User's Guide
Pin Signal Name
1 I1+
2 NC
3 T0H
4 T0L
5 4W01
6 IT01
7 T1H
8 T1L
9 GND
10 I1-
CJC sensor
11 I2+
12 NC
13 T2H
14 T2L
15 4W23
16 IT23
17 T3H
18 T3L
19 GND
20 I2-
21 +5V
22 GND
23 NC
24 NC
25 NC
26 NC
Use 16 AWG to 30 AWG wire for your signal connections.
Tighten screw terminal connections
When making connections to the screw terminals, be sure to tighten the screw until tight. Simply touching the
top of the screw terminal is not sufficient to make a proper connection.
Voltage input terminals (±V0H/V0L to ±V3H/V3L)
You can connect up to four voltage inputs to the voltage channels (V0H/V0L to V3H/V3L). The input range is
software programmable for ±10 V, ±5 V, ±2.5 V, or ±1.25 V. Each voltage channel is software configurable for
differential or single-ended mode.
When connecting differential inputs to floating input sources, you must provide a DC return path from each
differential input to ground. One way to do this is to connect a resistor from one side of each of the differential
inputs to GND. A value of approximately 100 k_ can be used for most applications.
Caution! All ground pins on the OM-USB-TEMP-AI (pins 9, 19, 22, 27, 30, 33, 36, 39, 49) are common
and are isolated from earth ground. If a connection is made to earth ground when using digital I/O
and conductive thermocouples, the thermocouples are no longer isolated. In this case,
thermocouples must not be connected to any conductive surfaces that may be referenced to earth
ground.

Sensor input terminals (T0H/T0L to T3H/T3L)

The OM-USB-TEMP-AI supports the following temperature sensor types:
Thermocouple – types J, K, R, S, T, N, E, and B
Resistance temperature detectors (RTDs) – 2, 3, or 4-wire measurement modes of 100 _ platinum RTDs.
Thermistors – 2, 3, or 4-wire measurement modes.
Semiconductor temperature sensors – LM36 or equivalent
OM-USB-TEMP-AI screw terminal descriptions
Pin Description
T0/T1 current excitation source
T0 sensor input (+)
T0 sensor input (-)
T0/T1 4-wire, 2 sensor common
T0/T1 2-sensor common
T1 sensor input (+)
T1 sensor input (-)
T0/T1 current excitation return
T2/T3 current excitation source
T2 sensor input (+)
T2 sensor input (-)
T2/T3 4-wire, 2 sensor common
T2/T3 2 sensor common
T3 sensor input (+)
T3 sensor input (-)
T2/T3 current excitation return
+5V output
Pin Signal Name Pin Description
27 GND
28 V3L
29 V3H
30 GND
31 V2L
32 V2H
33 GND
34 V1L
35 V1H
36 GND
37 V0L
38 V0H
39 GND
40 CTR
41 DIO7
42 DIO6
43 DIO5
44 DIO4
45 DIO3
46 DIO2
47 DIO1
48 DIO0
49 GND
50 NC
51 NC
52 NC
12
Signal I/O Connections
V3 voltage input (-)
V3 voltage input (+)
V2 voltage input (-)
V2 voltage input (+)
V1 voltage input (-)
V1 voltage input (+)
V0 voltage input (-)
V0 voltage input (+)
Counter Input
Digital Input/Output
Digital Input/Output
Digital Input/Output
Digital Input/Output
Digital Input/Output
Digital Input/Output
Digital Input/Output
Digital Input/Output