Measurement Computing WBK40 - Manual (Page 15)

WBK40 Block Diagram
Thermocouple Measurements
Each WBK40 and WBK41 module’s internal circuitry includes cold junction compensation (CJC) for direct
measurement of type J, K, T, E, N28, N14, S, R, and B thermocouples. The following table provides the
temperature range for each of these thermocouple types.
Thermocouple Temperature Ranges
T/C Type J K T E N28 N14 S R B
Temperature
Range °C -200 to
760 -200 to
1200 -200 to
400 -270 to
650 -270 to
400 0 to
1300 -50 to
1768 -50 to
1768 50 to
1780
Temperature
Range °F -328 to
1400 -328 to
2192 -328 to
752 -454 to
1202 -454 to
752 32 to
2372 -58 to
3214 -58 to
3214 122 to
3236
The modules automatically convert TC measurements into temperature readings, including cold-junction
compensation and linearization. Open TC detection and overload protection up to ±40V is also included on every
channel. To expand beyond the built-in 14 TC input channels, up to fifteen DBK84 expansion modules can be
attached to one WBK40 or WBK41, providing an additional 14 TC input channels per module.
Fifteen DBK84 Thermocouple Modules connected (via daisy-chain) to a single WBK40 or WBK41 module provide
up to 210 additional temperature channels, for a total system capability of 224 channels; i.e., 14 channels per device
x 16 devices.
If more than eight DBK84 modules are to be connected to one WBK40 [or WBK41] module,
additional power must be supplied. The power can be obtained from DBK32A or DBK33
Auxiliary Power Supply Cards, housed within a DBK10 expansion chassis.
In comparison to typical DBK options, the DBK84 modules demand significant power from the
system’s
±15 V power supplies. It is important that you calculate your system’s power demand, as
you may need to add auxiliary power supplies. Refer to the Power Management section of the
DBK Option Cards and Modules User’s Manual, in regard to calculating system power
requirements.
Note that WBK40 and WBK41 can each provide up to 15000 mW of power to DBK84 modules
that are added to the system. (See previous note regarding auxiliary power).
Thermocouple & Multifunctional Modules 926896 WBK40 & WBK41, pg. 15