B&K Precision 1739 - Manual - Manual (Page 23)

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6 Maintenance
WARNING
The following instructions are for use by qualified personnel only. To avoid electrical
shock, do not perform any servicing other than contained in the operating
instructions unless you are qualified to do so.
6.1 Fuse Replacement
If the fuse blows, the CV or CC indicators will not light and the power supply will not
operate. The fuse should not normally open unless a problem has developed in the
unit. Try to determine and correct the cause of the blown fuse, then replace only
with a fuse of the correct rating as listed below. The fuse is located on the rear panel
(see
Figure 2 ).
Line Voltage Fuse Type
120 Vac ± 10%, 50/60 Hz 1.5A Slow Blow
220 Vac ± 10%, 50/60 Hz 1.0A Slow Blow
Table 2 - Fuse Values
Line Voltage Conversion, International Units
The primary winding of the power transformer is tapped to permit operation from
120/220/230 or 240 VAC, 50/60 Hz line voltage. Conversion from one line voltage to
another is done by a simple position change of the fuse receptacle underneath the
line cord.
6.2 Adjustments
This unit was accurately adjusted at the factory before shipment. Readjustment is
recommended only if repairs have been made in a circuit affecting adjustment
accuracy, or if you have a reason to believe the unit is out of adjustment. However,
adjustments should be attempted only if a multimeter with an accuracy of ±0.02%
DCV or better is available (B&K Precision Model 5491B or equivalent).