LabVIEW

cancel
Showing results for 
Search instead for 
Did you mean: 

Grounding Thermocouples

Hallo,
We have an engine and we want to get some measurements of temperature from
the exhaust pipe(before and after a catalyst). The problem refers to
grounding the T/Cs.
The type of T/Cs is ground referenced and when the engine is off the
measurements are correct. When we turn on the key the measurements are
incorrect.
We use scxi-1000 with modules scxi-1100 and scxi-1112 connected to 6033E DAQ
card in differential mode and we have execute all the necessary adjustements
on the hardware about the grounding which are described in the manuals.
The problem is with the grounding or something else, and if so is there a
solution?

thank
you


GKonstan
Laboratory of Thermodynamics & Thermal
Engines
Departement of Mechanical & Industrial
Engineering
University of Thessaly,
Greece

http://www.mie.uth.gr/labs/ltte/ltte-eng/info/info.htm
0 Kudos
Message 1 of 2
(2,443 Views)
It sounds like you may be accidentally measuring some leakage current that is produced by the engine running. Measuring them in differential mode is good, but you may try grounding the negative side of the thermocouples themselves for further isolation.
0 Kudos
Message 2 of 2
(2,443 Views)