Maintenance – B&K Precision 1745A - Manual User Manual
Page 23

MAINTENANCE
23
CALIBRATION
If readjustment is required, use the following procedure. Locations
of the adjustments are shown in Fig. 11.
1. Set the front panel controls of the Model 1743BA as follows:
Coarse and Fine VOLTAGE controls fully clockwise. Coarse
and Fine CURRENT controls fully clockwise. Power switch to
On.
2. Connect the Multimeter to measure the voltage at pin 14 of IC2
with respect to the front panel red (+) output jack. Adjust R21
for -5.00 volts on the Multimeter.
3. Connect the Multimeter to measure the voltage at pin 8 of IC2
with respect to the front panel red (+) output jack. Adjust R64
for 0 + l 0 mV on the Multimeter.
4. Connect the Multimeter to measure the DC voltage between the
black (-) and red (+) output jacks. The voltage should be 35 to
37 volts, the green CV indicator should be lit, and the red CC
indicator should be off.
5. Set the front panel Fine VOLTAGE control for a reading of
35.00 volts on the Multimeter. Adjust upper GREEN R304 for a
front panel meter reading of 35.00 volts on the GREEN
VOLTAGE meter.
6. Set the front panel Coarse VOLTAGE control for a
reading of 04.00 to 06.00 volts on the GREEN
VOLTAGE meter.
7. Connect the Multimeter to read the DC current
between the black (-) and red (+) output jacks, using
the 10 amp range. The red CC indicator should light
and the green CV indicator should go off.
8. Set the front panel Fine CURRENT control for a
reading of 6.000 amps on the Multimeter. Adjust
lower RED R304 for a front panel meter reading of
6.000 amps on the RED CURRENT meter.
INSTRUMENT REPAIR SERVICE
Because of the specialized skills and test equipment
required for instrument repair and calibration, many
customers prefer to rely upon B+K Precision for this
service. We maintain a network of B+K Precision
authorized service agencies for this purpose. To use this
service, even if the instrument is no longer under
warranty,
follow
the
instructions
given
in
the
WARRANTY SERVICE INSTRUCTIONS section of
this manual. There is a nominal charge for instruments out
of warranty.