Measurement Computing USB-TEMP, Руководство пользователя

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5-1
Chapter 5
Specifications
Typical for 25 °C unless otherwise specified.
Specifications in
italic text are guaranteed by design.
Analog input section
Table 5-1. Generic analog input specifications
Parameter Conditions Specification
A/D converters Four dual 24-bit, Sigma-Delta type
Number of channels 8 differential
Input isolation 500 VDC minimum between field wiring
and USB interface
Channel configuration Software programmable to match sensor
type
Thermocouple ±0.080 V
RTD 0 to 0.5 V
Thermistor 0 to 2 V
Differential input voltage
range for the various sensor
categories
Semiconductor sensor 0 to 2.5 V
Absolute maximum input
voltage ±C0x through ±C7x relative to GND
(pins 9,19,28,38) ±25V power on, ±40 V power off.
Input impedance 5 Gigohm, min.
Open thermocouple detect disabled 30 nA max. Input leakage current
Open thermocouple detect enabled 105 nA max.
Normal mode rejection ratio f
IN
=
60 Hz 90 dB min.
Common mode rejection
Ratio f
IN=
50 Hz/60 Hz 100 dB min.
Resolution 24 bits
No missing codes 24 bits
Input coupling DC
Warm-up time 30 minutes min.
Open thermocouple detect Automatically enabled when the channel
pair is configured for thermocouple sensor.
The maximum open detection time is
3 seconds.
15 °C to 35 °C ±0.25 °C typ.,±0.5 °C max. CJC sensor accuracy
0 °C to 70 °C -1.0 to +0.5 °C max