HP 400E, Operating And Service Manual

Page: 13 / 57

Model 400E/EL
Section III
SECTION III
OPERATING INSTRUCTIONS
3·1. INTRODUCTION.
3-2. The ModeI400E/EL is primarily an ac voltmeter
and dB meter, but it can be used as an ac to dc
converter or as a wide band amplifier.
3-3. This section explains the controls of the
400E/EL and outlines the operating procedures for
each mode of operation.
3-4. LO C AT I O N O F C ONTROLS AND
INDICATORS.
3-5. Figure 3-2 shows the location of each of the
400E/EL controls and explains the function of each.
3-6.
OPERATING INSTRUCTIONS.
3-7. STANDARD 400E/EL.
3-8.
AC
Voltmeter.
Table 3-1. Effect of Distortion on Average
Responding Meter
%
ERROR
(*
Fundamental)
Harmonic
%
Distortion
Max. Max.
Positive Negative
Any
0.1
0.000
even 0.5 0.001
1.0 0.005
2.0 0.020
Third 0.1 0.033 0.003
0.5 0.168
0.167
1.0 0.338
0.328
2.0 0.687 0. 667
Fifth 0.1 0.020 0.020
0.5 0.101 0.099
1.0 0.205
0.195
2.0 0.420 1.380
*
Depends on phase relationship between
harmonic and fundamental.
a.
b.
NOTE
Since the 400E/EL is average
responding and rms calibrated, any
distortion will affect the accuracy
of the measurement. Table 3-1
shows t he errors caused by
distortion.
Ensure that 115/230
V
ac slide switch on
the rear panel matches line voltage used, and
connect power to the instrument. Mechani­
cally zero the instrument using the proce­
dure outlined in Paragraph 5-5.
To operate the ModeI400E/EL with battery
power, connect two 35 to 55 volt batteries
as shown in Figure 3-1. Since the front panel
LINE switch has no effect during battery
operation, the switch in Figure 3-1 can be
used as a convenient method of discon­
necting the batteries when the instrument is
not in use. Two 35 volt batteries will deliver
approximately 75 rnA and two 5 5 volt
batteries will deliver approximately 50 mAo
WARNING
For operator protection during battery opera­
tion, connect chassis tenninal (MP26) to earth
ground.
c. Turn line ON toggle switch to up position.
LINE lamp will glow.
d. Select approximate range of signal to be
measured.
Do not apply more than 500 volts ac to input.
Do not overload the. 001 through 1 volt ranges.
Consult Table 1-2
f
or overload limits. I
f
any o
f
these overloads are exceeded, the ins {rumen t
may be damaged.
3-1