ESI 250-DA - External Generator Terminals Connection; Detector Switch Functionality

1 .
CONTROLS
1.1
Circuit
Selector:
The
metal
lever
in
the
upper
right-hand
control
group
selects
the
bridge
circuit.
Panel
markings
indicate
the
circuit
chosen.
Two
inductance
measurement
circuits
are
provided;
inductors
can
be
measured
in
terms
of
their
equivalent
series
or
equivalent
parallel
circuit.
Two
resistance
multipliers
are
available;
the
XI
0
multiplier
is
included
to
extend
the
resistance
range.
For
capacitance,
two
D-multipliers
are
provided.
1
Z
Multiplier
Switch:
The
upper
right-hand
black
knob
selects
any
of
seven
multipliers.
The
pointer
indicates
the
value
of the
multiplier
and
the
type
of
units
used.
1.3
Main
Dial
Assembly:
The
lower
right-hand
DEKASTAT®
decade
resistor
dial
is
used
for
reading
the
value
of
resistance,
inductance
or
capaci-
tance
being
measured.
The
measured
value
is
given
by
the
product
of
the
DEKASTAT
reading
and
the
multiplier
reading.
For
resistance,
this
product
must
also
be
multiplied
by
the
circuit
selector
reading.
1 4
D-Q
Dial:
The
reading
of
the
large
left-hand
dial
times
the
D
or
Q
multiplier
reading
gives
the
value
of
D or
Q
at
one
kilocycle.
At
other
frequencies,
the
D
reading
for
C
or
Q
reading
for
L
series
must
be
multiplied
by
the
frequency
in
kilocycles,
and
the
Q
reading
for
L
parallel
must
be
divided
by
the
frequency
in
kilocycles.
1
5
Unknown
Terminals:
An
unknown
capacitor
is
connected
to
the
two
right-hand
terminals.
An
unknown
resistor
or
inductor
is
connected
to
the
third
and
fourth
terminals
from
the
right.
1.6
1.7
External
Generator
Terminals:
The
center
pair
of
terminals
are
for
connecting
an
external
generator
to
the
bridge.
External
D-Q
Terminals:
The
third
and
fourth
terminals
from
the
left
are
for
attaching
an
external
circuit
element
to
the D-Q
arm
of
the
bridge
for
special
measurements.
The
left-hand
external
D-Q
terminal
is
connected
to
the
bridge
chassis.
1.8
1.9
External
Detector
Terminals:
The
upper
left-hand
terminals
are
for
connecting
an
external
detector
to
the
bridge.
The
internal
ac
detector
is
connected
to
the
bridge
through
these
terminals
by
means
of
a
shielded
double
banana
plug
.
>etector
Switch:
The
switch
in
the
lower
left-hand
corner
of
the
bridge
5
for
choosing
the
detector.
In
the
ac
or
external
detector
posiUon,
he
detector
corners
of
the
bridge
are
connected
to
the
externel
detector
erminals.
In
the
shunted
meter
position,
the
detector
corners
of
the
.ridge
are
connected
to
the
galvanometer
through
a
shunting
network,
n
the
direct
meter
position,
the
bridge
is
connected
directly
to
the
meter.
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