Omega CL27, CL24, CL25, CL23A, CL26 manual Data Logging and Recall

WHT

BLK

GRN

RED

Figure 6. 4-Wire Resistance Measurement

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, 100Ω and 1000Ω 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.

15