Comet MS6D, Инструкция по эксплуатации, Страница: 16 / 56

16 ie-ms2-MS6-10
Connection of thermocouple probes

connect thermocouples in the same way as voltage signals. Use shielded thermocouple wires for
longer distances.

each wire between data logger and thermocouple must be from proper thermocouple material

for extension use compensation cable designed for applied thermocouple - thermocouples cannot be
extended by usual copper leads !
Marking of subminiature thermocouple connectors and wires manufactured by OMEGA (in
accordance with US standard):
Type of thermocouple Connector color + wire color - wire color
K (NiCr-Ni) Yellow Yellow Red
J (Fe-Co) Black White Red
S (Pt10%Rh-Pt) Green Black Red
B (Pt30%Rh-Pt) White Black Red
T (Cu-CuNi) Blue Blue Red
N (NiCrSi-NiSiMg) Orange Orange Red
If there are more thermocouple inputs in data logger not galvanically isolated, avoid thermocouples
to be mutually connected. If hazard of current leakage exists (mostly between thermocouple
welded point and surrounding metal framework), thermocouple probes with galvanic isolated weld
from outer probe shield or other measuring method should be used (e.g. external
thermocouple/current loop transducers with galvanic isolation). In other case high measuring errors
can appear.
Warning - cold junction temperature is sensed at area between channel 8 and channel 9, where the
accuracy and the measuring stability is best. If using thermocouples, mind correct data
logger working position (vertically, input terminals downward and sufficient ambient air
flow). In no case install data logger with thermocouples horizontally, to the rack and to
places with temperature fluctuations. Avoid higher input voltage than ±10V. Also
avoid
short circuits of terminals +Up with COM or GND. All such circumstances cause
undesired temperature fluctuation and influence temperature measurement of
thermocouple cold junction and this way also result temperature measurement!