American Magnetics 420 Power Supply Programmer - Manual (Page 114)

96 Rev. 7
Service
Troubleshooting Hints
5.2.1 The Model 420 does not appear to be energized with the
power switch in the
32:(5 ( , ) position.
1. Ensure that the Model 420 is energized from a power source of
proper voltage.
Warning
If the instrument has been found to have been connected to an
incorrect power source, return the instrument to AMI for evaluation
to determine the extent of the damage. Frequently, damage of this
kind is not visible and must be determined using test equipment.
Connecting the instrument to an incorrect power source could
damage the internal insulation and/or the ground conductors,
thereby, possibly presenting a severe life-threatening electrical
hazard.
2. Verify continuity of the line fuse, F1, located on the instrument
printed circuit board.
Warning
This procedure is to be performed only when the instrument is
completely de-energized by removing the power-cord from the power
receptacle. Failure to do so could result in personnel coming in
contact with high voltages capable of producing life-threatening
electrical shock.
a. Ensure the instrument is de-energized by disconnecting the
power cord from the power source. Disconnect the power cord
from the connector located on the rear panel of the instrument.
b. Remove the instrument top cover and check the fuse F1 for
continuity.
c. If the fuse is bad, replace with a fuse of identical rating.
Caution
Installing fuses of incorrect values and ratings could result in
damage to the instrument in the event of component failure.
Note
The proper fuse for this instrument is an IEC Type F, 5x20mm fuse
rated for 0.315 Amperes, quick acting. The fuse will be labeled with
the current rating and marked with an F, or red color code to denote
quick acting.