User`s guide

Universal Library User's Guide Temperature Input Boards - USB-5203, USB-5201
190
Pacing temperature readings
The internal update rate for temperature measurement is a fixed value for these devices. If the UL reads the
device faster than the internal update rate, temperature readings "repeat." For example, if using cbTIn() in a
loop to measure a rapidly changing temperature, readings do not change for several iterations of the loop, then
"jump" when the update occurs internally.
Using single sensors with cbTInScan()
When using single sensors for RTD or thermistor sensors, you should ignore the data for channels that do not
have sensors attached. It is best to use cbTIn() for these configurations, since you can select which channels
to read. If you use cbTInScan(), however, data for all channels over the entire range of channels are returned.
Since some channels are not populated in this configuration, you should filter out the data for channels
without sensors.
Saving configuration settings
InstaCal allows you to save USB-5203 and USB-5201 configuration settings to a file, or load a configuration
from a previously saved file.
 Each USB-5203 channel can be configured to measure temperature data collected by one of five
categories of temperature sensors: thermistors, thermocouples (one of eight types), RTDs,
semiconductors, and Disabled.
 Each USB-5201 channel can be configured to measure temperature data collected by one of eight types of
thermocouples.
Recommended warm-up time
Allow a warm-up time of 30 minutes before taking measurements. This warm-up time minimizes thermal drift
and achieves the specified rated accuracy of measurements.
For RTD or thermistor measurements (USB-5203 only), this warm-up time is also required to stabilize the
internal current reference.
Calibration
Any time the sensor category is changed in the configuration for the USB-5203, a calibration is automatically
performed by InstaCal. If the device has not been warmed up when this occurs, you should re-calibrate after
the specified warm-up time.
Error codes
 The UL returns -9999 when a value is out of range or an open connection is detected.
 The UL returns -9000 when the device is not ready. This usually occurs right after the device is powered
up and calibration factors are being loaded.
Miscellaneous functions and methods supported
UL: cbFlashLED()
UL for .NET: FlashLED()
Causes the LED on the side of the module to blink twice for visual identification.
When you have several modules connected to the computer, use these functions to identify a particular
module by making its LED blink.