Thermocouple meters (Fig. 2) convert applied current (a-c or d-c) by thermoelectric effects into deflection currents which register on a PM moving-coil couple actuated by heat generated at the junction formed by two strips of dissimilar metal. One strip carries the heat-generating input currents, the other carries heat-produced currents to the meter movement.
Thermocouple meters are used to measure a wide range of either a-c or d-c currents and give an accurate picture of the effective, or heats producting, value of a current no matter what its nature. The meters are relatively expensive and the thermal delay in converting input electricity to heat makes them sluggish.
b) Place a transparent film on the text and insert every fifth word (22) which is shaded on the film.
c) Fill in the blanks in such a way that it makes sense.
1. The convertion of applied current into deflection current is through a thermocouple.... a) actuated by two strips of dissimilar metal; b) actuated by heat generated at the junc tion; c) generated by input currents.
2. Thermocouple meters are used to... . a) measure voltage by the comparison method; b) operate thro ugh the electrostatic repulsion; c) measure a wide range of either a-c or d-c currents.
3. Thermocouple meters are relatively. ... a) expensive; b) large; c) cheap.
Now record your time and results 22—20 correctly inserted words+3 correct answers per 8 minutes get you an excellent mark.
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