Omega Engineering OMB-DBK-34A, User Manual

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DBK9 8-Channel RTD Card
Overview …… 1
Hardware Setup …… 2
Card Connection …… 2
Card Configuration …… 2
DBK9 Calibration …… 3
DaqBook /100 Series & /200 Series and DaqBoard [ISA type] Configuration …… 3
DaqBook/2000 Series & DaqBoard/2000 Series Configuration …… 3
Software Setup …… 3
DBK9 – Specifications …… 3
Reference Notes :
o Chapter 2 includes pinouts for P1, P2, P3, and P4. Refer to pinouts applicable to your
system, as needed.
o In regard to calculating system power requirements, refer to DBK Basics located near
the front of this manual.
Overview
Temperatures sensed by RTDs are attached to the LogBook or the Daq Device through the DBK9 RTD
expansion card.
Up to eight RTDs can attach to each DBK9 and up to 8 DBK9s can attach to the LogBook or the Daq
Device for measuring a maximum of 256 temperatures. The DBK9 card supports 3- or 4-wire RTDs and
operates by reading 3 voltages and using them in the following equation:
RTD = [Va - Vd - 2(Va - Vb) Rsense] / Vd (Result in Ohms)
Where: Rsense = 100
Ω
(a constant derived from the actual hardware)
The result of this equation is converted into a temperature via software (using a complex formula and
lookup tables). The DBK9 features an on-board Programmable Gain Amplifier for measuring 100
Ω
,
500
Ω
, or 1000
Ω
type RTDs. For each RTD, the DBK9 can measure temperatures in a range of
-200 to +850°C.
DBK Option Cards and Modules
879895
DBK9, pg. 1