Omega 24 Manuale Utente

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Lead resistance errors are compensated for in 3-wire configurations.
However full compensation requires equal resistance in each lead. This
configuration is common with 100-ohm RTDs.
In 4-wire configurations, accuracy is unaffected by lead resistance, and
resistance differences between leads.
NOTE: These instruments measure input voltages on all 4 termi-
nals, and are able to distinguish between 2-4 and 3-wire hookups.
Switching between these measurement modes is automatic.
2. Set instrument to METER mode.
3. Use the sensor-select key to set the instrument to the appropriate func-
tion and range.
NOTE: Due to limited display area, 100
Ω
and 1000
Ω
RTD's are
indicated on the display by a momentary readout of "RTD-100"
(or "RTD-1000") when first selected.
Thermistors are identified by a momentary alpha-numeric readout
of "Y-400" (signifying YSI Series-400 type thermistor).
Any of these readouts can be recalled by turning the unit off and
back on.
5. DATA LOGGING AND RECALL
Operating as a meter, the unit can save and recall up to 10 readings (each
with independent parameters: eg. °F/°C, TC-type and resolution) in random
access memory.
Figure 6. 4-Wire Resistance Measurement
WHT
BLK
GRN
RED