Fluke 2625A User Manual

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Diagnostic Testing and Troubleshooting (2620A/2625A)
Analog Troubleshooting
5
5-17
A3TP13 TO A3TP9
0
1V/DIV
5 mS/DIV
s37f.eps
Figure 5-6. Integrator Output
5-11.  DC Volts Troubleshooting
Setup the instrument to measure a specific channel on the 300 mV or 3V range, and
apply an input to that channel. Then trace the HI signal (referenced to the input channel
LO terminal) as described in Table 5-4.
If the input HI path traces out properly, remove the input from the channel and trace
continuity through the LO path. Check among A3L4-A3L24, A3K1-A3K14, A3R35,
A3R43, and A3U8 pin 11.
Table 5-4. DC Volts HI Troubleshooting
Checkpoint
Signal Description
Possible Fault
A3R11 HI
Input
A3K1 through A3K14, A3U4, A3U5, A3U11, A3U12,
A3L1, A3L2, A3L3
A3U8 pin 23
Input
A3R11, A3K17, A3R42, A3C32
A3U8 pin 58
Input, DC filter output
A3U8, A3Q2
5-12.  AC Volts Troubleshooting
Setup the instrument to measure a channel on the 300 mV ac range, and apply a signal to
that channel. Then trace this HI signal (referenced to the input channel LO terminal) as
described in Table 5-5.
If the input HI path traces out properly, remove the input from the channel, and trace
continuity through the LO path. Check among A3L4 through A3L24, A3K1 through
A3K14, A3R43, A3R34, A3K16, and A3U8 pin 13.