343A
OPERATING INSTRUCTIONS
2-1. INTRODUCTION
2-2.
This section
contains operating instructions
and
applications
infromation
for the Model 34 1 A and
Model
343A
Voltage Calibrators. Unless
otherwise specified,
all
instructions apply
to both instruments.
2-3.
If any problem is
encountered in
operating the
instrument,
contact the nearest
John Fluke Sales
Repre-
sentative or write
directly to the John Fluke
Manufactur-
ing
Company. Please include the
instrument serial number
when
writing.
2-4.
OPERATING FEATURES
2-5
.
The following paragraphs
describe instrument con-
trols and power
requirements.
2-6. CONTROLS, TERMINALS,
AND
INDICATORS
2-7.
The
name
and
function of
the front and rear
panel
controls, terminals, and
indicators are
shown in Figure
2-1.
2-8. INPUT POWER
REQUIREMENTS
2-9. The instrument
operates on either 1 15 or 230
volt
ac power,
and is normally
supplied with
connections for
11.5
volt use. Dual primary
windings
in
the power trans-
former permit ready
conversion
from
one
operating voltage
to the
other. The
conversion procedure is
described in sec-
tion
IV, paragraph
4-18.
2-10, PRELIMINARY
OPERATION
2-11. The
following paragraphs
describe preliminary
connections,
control settings,
adjustments and
safety pre-
cautions,
which should be observed
before operating the
instrument.
2-12,
AC
LINE CONNECTIONS
2-13. Connect the
Model 341
A/343
A line plug to a
1 1 5 volt ac (or to
230 volts ac if
the instrument is so
wired), 50 to 440 Hz,
single phase, three-wire
outlet.
WARNING!
The
round pin on the
polarized three-prong
plug connects the
instrument case to power
system ground.
Verify that the ac outlet is pro-
vided with the earth ground
wire normally
found
in a three wire
single-phase connector.
If the third wire is
not present in the outlet
or if a
three-to-two-wire adapter is used,
ensure
that
the instrument ground wire is
connected
to a high
quality earth ground.
2-14.
SENSE
CONNECTIONS
2-15.
When
a
load is connected to
the Model
341
A
/
343A,
there may be an
appreciable voltage drop between
the
instrument
and
the load due to the resistance of
the
connecting leads. The
nomograph shown in Figure
2-2
can
be used to determine the
approximate voltage de-
veloped in the leads. If the
voltage
drop
is excessive,
the instrument can then be connected for
remote sensing.
2-16.
Using
The Nomograph.
With
a straight
edge,
connect
the
point representing output current on
scale
1 to the point representing the
gauge of the connecting
wires on scale 2. The
voltage developed
in the
connecting
wires, expressed in
millivolts
per foot, is
read
on.
scale 3.
To
determine the total voltage
developed
in the
connecting
leads,
multiply
the total length in
feet
by
the value ob-
tained from scale 3. For example, assume that
two AWG
2-1
To Next Page
Loading...
