Page 300 - Electrician - TT (Volume 1)

ELECTRICIAN - CITS

Figs 2 & 3

The principle and working of an induction type wattmeter are similar to the induction type energy meter. The only
difference in construction between the energy meter and wattmeter is that the spindle of the wattmeter is spring-
controlled, has a pointer but no train of gears.
However to summarise what has been learnt earlier the following table 1 is provided with connection diagram of
3- phase wattmeter Fig 4, Fig 5 & Fig 6
Table 1

Sl.No. Types of 3-phase wattmeter Circuit diagram Application
1 2-element 3-wire type Fig 4 Balanced and
unbalanced
loads

2 3-element 3-wire type Balanced loads.
Fig 5

287

CITS : Power - Electrician & Wireman - Lesson 50-53 CITS : Power - Electrician & Wireman - Lesson 50-53