Lab mannaul



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2. Sensitiveness = 2. [(N2 -N1) / (N1 + N2 ) ] .

3. Governor effort, Q = (W + w). C N

4.Governor power,P = Q. x Nm
3) Hartnell Governor :-





DATA OF GOVERNOR :-



  1. Stiffness of springs = 7007 N/m.

  2. Length of vertical arm of ball crank lever, a =0.080m

  3. Length of horizontal arm of ball crank lever, b = 0.130m.

  4. Initial radius of rotation, r0 = 0.165 m.

  5. Mass of sleeve assembly, M = 3.2 kg.

  6. Total mass of balls, m = 0.5 kg.

Total weight of balls, w =4.9 N.

  1. Compression of spring, CI = 3 mm.


CALCULATIONS :-

Let spring stiffness be S and initial compression of spring be C1 m

Radius of rotation at speed N1-

R1 = 0.165+d1m


Where, d1 = x1. (a/b)


  1. Controlling force :-

w = 27N/60

Fc= m.ꞷ12r1, Newton. (Where, in = 0. 5 Kg)

Also, this force is balanced by weight of sleeve and spring pressure. If F, is spring force, then,

Taking moments about fulcrum of bell crank lever,

Fc . a = ( W + Fs ) . b

W + Fs = Fc . (a/b )

W + S (x1 + C1) = Fc .(a/b )

Fs = S ( x1 + c1)


  1. Sensitiveness = 2 . [ ( N2- N1) / ( N1 + N2 ) ]




  1. Governor effort , Q = c ( W + Fs ) Newton.

C = Percentage increment in speed( in fraction ) = ( N2 – N1 ) / N1



  • 4. Governor power, P = Q . x. N-m



GRAPHS :- Plot the graph of controlling force vs. radius of rotation.
PRECAUTIONS :-

1, Operate all the switches and controls gently. Especially, operate the speed control slowly. Never move it forward / backward harshly.



  1. While fixing the governor assembly, properly tighten the nut over the top of the spindle and nuts of the pins inserted in sleeve holes.

  2. Do not tamper with the other nut - bolts of the unit.

  3. Never interchange the electric wires connected to the armature and field winding of the driving motor.

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