Question

Given a moving coil type measuring unit with: Internal resistance R= 1 kq; current for end-of- scale deflection in=0.01 mA. 41 [V] -411 [V] Using this unit, design a DC V-meter to show a half-scale deflection under the periodic input voltage given in the figure and having an internal resistance of R=10 kn/v.

Answer 1

Peak value of periodic input voltage is given as 40 [v] [see 4 *[v] [see the given ware foom] i.e. = 4* v DC such volt-meter Cu-meter) is to be designed that it will show hadf-scale deflection, The movicoil coid will read Dc ie the avarage value of periodic wave form [full-scale 2 Vm Hence, Voc Varg. un [half-scale Voc vang T & Voca 4 ñ volt. T [half-scale ..unca 4 v as internal of voltmeter for Ro, i lokalu 80kr (for full scale) but sensitivity resistance is given Toteel interneel Resistance, Rui Rr' But, the measuring unit is given with In (o-0.01 mA) of current with an internas of Ri Elks resistance Venetes is ce D C with the abone unit hence a series seerstanee to be designed v-meter neith series to the is to be added Avi Rse POKL 0.01MA 4 060-80) F.S. (0-4 v) His. 80-8.24 Ikan Ri 4 v Co.ormA) CRY + Rvs + Ase) 24V (o.oma , Cikrt ooks & Ree) 4 v > OLMA) C 81ks + Ree) 4U (ooin) Colk) v Rse C 0.01 MA) (4- 0.812v 3.19 Rse 0.01 MA Rse 319ko for halfase ale deflection Hene is required a 319 kr series resistance of the rometer, to design respective