Fluke 5500A, Service Manual

Page: 68 / 296

5500A
Service Manual
3-14
3-15. Capacitance, Four-Wire Comp
This step measures the internal capacitance between the 5500A AUX HI and NORMAL
LO terminals to give the best COMP four-wire
operation in Capacitance.
Refer to Figure 3-6. Connect the LCR meter INPUT/SENSE HI to the 5500A AUX HI;
connect the LCR meter INPUT/SENSE LO to the 5500A NORMAL LO. Enter the LCR
reading into the 5500A when prompted. The LCR meter should nominally read 400 pF
with a 1 kHz, 2 V rms stimulus.
Note
Make sure there are no other connections to the 5500A, especially the
SCOPE BNC. Connecting any additional grounds to the 5500A can cause
erroneous capacitance outputs.
POWER
I
O
0 •
1 2 3
4 5 6
7 8 9
ENTER
M
k
m V Hz
FIELD
EDIT
/
+
F
OPR EARTH SCOPE BOOST MENU
PREV
SHIFT
RESET
CE
SETUP
REF
NEW
TC
MEAS
¡F
µ
n
p
W
dBm sec
¡C A
MULT
x
DIV
÷
OUT
TRIG
5500A CALIBRATOR
20V PK
MAX
HI
LO
TC
TRIG
OUT
1000V
RMS
MAX
20V
RMS
MAX
1V PK
MAX
20V PK
MAX
NORMAL AUX
SCOPE
V, ,
RTD
A, -SENSE,
AUX V
200V PK
MAX STBY
5500 A
Input sense high to AUX high.
Input sense LO to normal LO.
PM6304C
om013f.eps
Figure 3-6. Connections for Four-Wire Compensated Capacitance
Note
The remaining steps in the calibration procedure are not necessary unless
the 5500A has been repaired. They are called “Factory Cal,” and are
accessible only via the remote interface.
3-16. Frequency
Frequency calibration is only accessible by remote command. See “Remote Commands
for 5500A Calibration,” later in this chapter. In remote, you can jump to Frequency
calibration by sending the command:
CAL_START FACTORY
In Frequency calibration, the 5500A outputs 3 V, 500 kHz. Measure the frequency with a
precision counter. Enter the frequency reading into the 5500A when prompted by the
5500A.