Omega OM-USB-TC-AI, User Manual

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OM-USB-TC-AI User's Guide Signal I/O Connections
11
OM-USB-TC-AI screw terminal descriptions
Pin Signal Name Pin Description Pin Signal Name Pin Description
1 RSVD Reserved, Do Not Use 27 GND
2 NC 28 V3L V3 voltage input (-)
3 T0H T0 sensor input (+) 29 V3H V3 voltage input (+)
4 T0L T0 sensor input (-) 30 GND
5 4W01 T0/T1 4-wire, 2 sensor common 31 V2L V2 voltage input (-)
6 RSVD Reserved, Do Not Use 32 V2H V2 voltage input (+)
7 T1H T1 sensor input (+) 33 GND
8 T1L T1 sensor input (-) 34 V1L V1 voltage input (-)
9 GND 35 V1H V1 voltage input (+)
10 RSVD Reserved, Do Not Use 36 GND
CJC sensor
11 RSVD Reserved, Do Not Use 37 V0L V0 voltage input (-)
12 NC 38 V0H V0 voltage input (+)
13 T2H T2 sensor input (+) 39 GND
14 T2L T2 sensor input (-) 40 CTR Counter Input
15 4W23 T2/T3 4-wire, 2 sensor common 41 DIO7 Digital Input/Output
16 RSVD Reserved, Do Not Use 42 DIO6 Digital Input/Output
17 T3H T3 sensor input (+) 43 DIO5 Digital Input/Output
18 T3L T3 sensor input (-) 44 DIO4 Digital Input/Output
19 GND 45 DIO3 Digital Input/Output
20 RSVD Reserved, Do Not Use 46 DIO2 Digital Input/Output
21 +5V +5V output 47 DIO1 Digital Input/Output
22 GND 48 DIO0 Digital Input/Output
23 NC 49 GND
24 NC 50 NC
25 NC 51 NC
26 NC 52 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 kΩ can be used for most applications.
Caution!
All ground pins on the OM-USB-TC-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.
Thermocouple input terminals (T0H/T0L to T3H/T3L)
You can connect up to four thermocouples to the differential sensor inputs (T0H/T0L to T3H/T3L). The OM-
USB-TC-AI supports type J, K, R, S, T, N, E, and B thermocouples. You can mix thermocouple types (J, K, R,
S, T, N, E, and B).