Pulley-Driven Generator or Alternator.

ternator it will be necessary to establish a speed

t h e high speed driving head (4, fig.

7 ) . Follow mounting procedures pre-

(rpm) for the generator or alternator and make

certain adjustments to the tachometer indicator

circuitry so the tachometer indicator meter (3)

(3) T u r n the tachometer indicator high-

will indicate this speed (rpm). After complet-

low switch (18) to the "LOW" posi-

i n g these adjustments, any variation in the

tion and the tachometer indicator

speed (rpm) of the pulley driven generator or

d i r e c t - d r i v e calibrating potentiometer

alternator will be indicated on the tachometer

switch (19) to the "DIRECT DRIVE"

i n d i c a t o r meter. To make these adjustments

position.

proceed as follows:

(4) S t a r t the varidrive assembly as pre-

(1) Obtain the rated speed (rpm) of the

s c r i b e d in paragraph 93. Preset the

generator or alternator to be tested,

s p e e d (rpm) of the pulley (drivers)

( 8 , fig. 20) by adjusting the speed

m a n u f a c t u r e r ' s literature or name-

(rpm) of the varidrive assembly to a

plate data on the generator or

c a r d i n a l point on the tachometer in-

alternator.

dicator meter (3) using the speed con-

(2) If the rated speed is below 3,300 rpm,

t r o l (32). For example: If the gen-

m o u n t the generator or alternator on

erator or alternator is mounted on the

the low speed driving head (5, fig. 7).

low speed head, select a point on the

t a c h o m e t e r indicator meter (reading

If the rated speed is above 3,300 rpm,

m o u n t the generator or alternator on

on lower scale) in the vicinity of 2,000