Table of Contents
Advertisement
When the test is over, the instrumentation should be switched off by first
turning the
((Output Voltage" knob
to
((0" and
then disconnecting the power
amplifier,
the
Exciter Control and
the field
coil supply from
the mains by
means of their
various "On-Off" switches.
Operation at Constant Velocity Level.
Constant velocity level
control
is
only
possible by means
of
a velocity type
pick-up. The
frequency
range
available
for
velocity
level
control
is
5-2ooo
cps, and
the level
ranges are
o.1 inch/sec., 1
inch/
sec., 10 inch/sec.,
and
100 inch/sec. The
various
ranges
are
found by multiplying the numbers on
the left-hand
side of the "Displacement-Velocity
Range"
switch
by ten
).
To
set
up the test
apply
the
following
procedure:-
1. Follow instructions item 1 through 11 under
"
Operation
at Constant
Displacement Level".
(Page
17).
2. Set "Function Selector"
to
"
Vel.".
3.
Set
"
Displacement-Velocity Range" to the desired
velocity
level range.
(The
actual
velocity
level range
corresponds
to the numbers marked on
the left-hand
side
of the knob when multiplied by ten).
Note: The
level ranges o.1 inch/sec., 1
inch/sec.,
10
inch/sec.,
and
100
inch/sec. indicate full-scale meter deflection peak value
velocity.
4. Follow
the instructions item 14 through 18 under
"
Operation
at Constant
Displacement
Level",
page 18.
Operation at Constant Acceleration Level.
Constant
acceleration level
operation can
be
obtained
by using
either an
accelerometer or a velocity
type
pick-up as
the
controlling element.
The
available
frequency
and
level
ranges
are:-
I
With Accelerometer
I
With
Vel~city
Level
Ranges
Control
Pick-up
Control
1-
10-
100
and
10-10ooo
cps
10-
2ooo cps
1ooo G
*)
G*)
=
acceleration of gravity
(981
cm/
sec.2 or
386 inch/sec.
2 ).
To set
up the
tes
t,
apply
the
following
procedure:-
1.
Follow instructions
item 1 through 10 under
"
Operation
at Constant
Displacement
Level". Page 17.
2. Set
"Function
Selector"
to
"Accel.".
Hl
Advertisement
Table of Contents
