Operating Instructions; Introduction; Meter Mechanical Zero Adjustment (400F Only); Ac Voltage Measurements - HP 400F Operating And Service Manual

Model 400F /FL

3-1. INTRODUCTION.

3-2. This section contains instructions and information
necessary for the operation of the 400F/FL AC Volt­
meters. Included is identification of controls� indi­
cators and connectors. turn on proceduresiand oper­
ating instructions.
3-3. CONTROLS, INDICATORS AND
CONNECTORS.
3-4. Each control� indicator, and connector on the
400F/FL is identified and described in Figure 3-1.
3-5. METER MECHANICAL ZERO ADJUSTMENT
(400F ONLY).
3-6. The mechanical zero adjustment i s located in
the center of the instrument front panel. If the meter
pointer does not indicate zero after the instrument has
been off at least one minute. mechanically zero the
meter. following the steps outlined below.
a. Turn instrument power off. and allow at least
one minute for meter pointer to stabilize.
b. Rotate zero adjustment screw clockwise until
pointer is left of zero and moving upscale.
c. Continue rotating screw clockwise
pointer is at zero. Stop when pointer is exactly
on zero. Iipointer overshoots, repeat step b.
d. When pointer is exactly over zero, rotate
adjustment screw slightly counterclockwise to
relieve tension on pointer suspension.
pointer moves to the left. repeat whole pro­
cedure, but make counterclockwise rotation
less.
3-7.
TURN ON PROCEDURES.
a. If line voltage is used, ensure that the 115-230
vac switch (located on the rear panel) is in the
correct position.
switch to the ON position.
will glow, indicating
applied.
b. If batteries are used,
volt batteries as shown in Figure 3-2.
line ON switch is not in the circuit when bat­
teries are used, therefore an external DPST
switch should b e used to provide a means for
disconnecting the batteries when the instru­
ment is not in use.
01795-2
SECTION
OPERATIN G
until
If
Turn the line ON toggle
The LINE lamp
that line power is
connect two 35 to 55
The
III
INSTRUCTION S
BATTERY VOLTAGE
35-55
-11
(35-55V)
Figure 3-2.

External Battery Connection

3-8.

AC VOLTAGE MEASUREMENTS.

Since the 400F/FL is average re­
sponding and rms calibrated,
distortion will affect the accuracy of
the measurement. Table 3-1 shows
the errors caused by distortions.
Table 3-1. Effect of Distortion on Average Respond­
%
HARMONIC
DISTORTION
Any even 0.1
0.5
1.0
2.0
Third 0.1
0.5
1.0
2.0
Fifth 0.1
0.5
1.0
2.0
*Depends on phase relationship between harmonic
and fundamental.
Section ID
35-55
+
_ _ _
_11
+ +
92 91
(35-55V)
any

ing Meter

%
ERROR
Fundamental)
(
'
MAlL
MAlL
NEGATIVE
0.000
0.001
0.005
0.020
0.033 0.033
0.168 0.167
0.338 0.328
0.687 0.667
0.020 0.020
O.
101 0.099
0.205 0.195
0.420 0.380
3-1