![background image](http://html2.mh-extra.com/html/omega/om-usb-temp-ai/om-usb-temp-ai_user-manual_5155124021.webp)
Chapter 5
Specifications
All specifications are subject to change without notice.
Typical for 25 °C unless otherwise specified.
All specifications apply to all temperature and voltage input channels unless otherwise specified.
Specifications in italic text are guaranteed by design.
Analog input
Table 1. Generic analog input specifications
Parameter
Conditions
Specification
A/D converter type
T0x-T3x, V0x-V3x
AD42_321
Dual 24-bit Sigma-Delta
Voltage input
V0x-V3x
4 differential
4 single-ended
Number of channels
Temperature input
T0x-T3x
4 differential
Input isolation
500 VDC minimum between field wiring and USB
interface
T0x-T3x
Temperature input.
Software programmable to match sensor type
Channel configuration
V0x-V3x
Voltage input
Power up and reset state
Factory default configuration is Disabled mode.
Once configured, each channel reverts to the mode
previously set by the user.
Single-ended
Vx_H inputs are connected directly to their screw
terminal pins.
Vx_L inputs are disconnected from their screw
terminal pins and internally connected to GND.
Vx_H and Vx_L inputs are connected directly to
their screw terminal pins.
Analog input modes
Differential
Tx_H and Tx_L inputs are connected directly to their
screw terminal pins.
Thermocouple
T0x-T3x
±0.080 V
RTD
T0x-T3x
0 to 0.5 V
Thermistor
T0x-T3x
0 to 2 V
Semiconductor sensor
T0x-T3x
0 to 2.5 V
Input ranges
Voltage
V0x-V3x
±10 V, ±5 V, ±2.5 V, ±1.25 V
software selectable
T0x-T3x relative to GND
(pins 9, 19, 22, 27, 30, 33, 36, 39, 49)
±25 V maximum (power on)
±40 V maximum (power off)
Absolute maximum
input voltage
V0x-V3x relative to GND
(pins 9, 19, 22, 27, 30, 33, 36, 39, 49)
±25 V maximum (power on)
±15 V maximum (power off)
Input impedance
T0x-T3x
5 Gigohm (power on)
1 Mohm (power off)