Spectrum Controls 1746sc-NI8u User Manual
Page 87

Appendix A: Module Specifications
75
RTD Conversion
JIS C 1602-1997 for Pt 385
JIS C 1604-1989 for Pt 3916
SAMA RC21-4-1966 for the 10
Ω
Cu 426 RTD
DIN 43760 Sept. 1987 for the 120
Ω
Ni 618 RTD
MINCO Application Aid #18 May 1990 for the 120
Ω
Ni 672 RTD
Thermocouple
NIST ITS-90 standard
Linearization
Channel Multiplexing
3 mS
Settling Time
RTD Current Source
200µA, one for each RTD channel
Cold Junction
Accuracy ±1.72°C, -25°C to +105°
Compensation
On board CJC Sensor Required, Analog Devices AD592CN
Input Impedence
Greater than 10M
Ω
> Ohm Voltage / Thermocouple / RTD
< 250
Ω
current
Temperature Scale
°C of °F and 0.1°C or 0.1°F
(Selectable)
DC Millivolt Scale
0.1 mV, 0.01 mV, or 0.001 mV
(Selectable)
Depending on input type
Milliamp Scale
.01 mA or .001mA
(Selectable)
Open Circuit Detection
Upscale, Downscale, Zero, or Disabled
(Selectable)
Does not apply to 5 or 10V range, or 0-20mA input type
Time to Detect
One module update time
Open Circuit
Input Step Response
0 to 95% in 300 msec (10 Hz)
Display Resolution
See Channel Data Word Resolution table in Chapter 4
Overall Module Accuracy See Module Accuracy Tables below
@ 25°C (77°F)
Overall Module Accuracy See Module Accuracy Tables below
(0°C to 60°C, 32°F to 140°F)
Overall Module Drift
See Module Accuracy Tables below
Module Update Time
Dependent upon enabled channels (see Update Time, Chap 3)
Channel Turn-Off Time
Up to one module update time
Overall Accuracy
The accuracy of the module is determined by many aspects of the
hardware and software functionality of the module. The following
attempts to explain what the user can expect in terms of accuracy based
on the thermocouple, RTD, resistance, and millivolt, volt, and milliamp
inputs for the NI8u module.