HP 8921A Programmer's Manual page 5

Safety Considerations for this Instrument
WARNING: This product is a Safety Class 1 instrument (provided with a protective earthing
ground incorporated in the power cord) The mains plug shall only be inserted in a
socket outlet provided with a protective earth contact. Any interruption of the
protective conductor inside or outside of the product is likely to make the product
dangerous. Intentional interruption is prohibited.
Whenever it is likely that the protection has been impaired, the instrument must
be made inoperative and be secured against any unintended operation.
If this instrument is to be energized via an autotransformer (for voltage
reduction), make sure the common terminal is connected to the earth terminal of
the power source.
If this product is not used as specified, the protection provided by the equipment
could be impaired. This product must be used in a normal condition (in which all
means for protection are intact) only.
No operator serviceable parts in this product. Refer servicing to qualified
personnel. To prevent electrical shock, do not remove covers.
Servicing instructions are for use by qualified personnel only. To avoid electrical
shock, do not perform any servicing unless you are qualified to do so.
The opening of covers or removal of parts is likely to expose dangerous
voltages. Disconnect the product from all voltage sources while it is being
opened.
Adjustments described in the manual are performed with power supplied to the
instrument while protective covers are removed. Energy available at many points
may, if contacted, result in personal injury.
The power cord is connected to internal capacitors that my remain live for
5 seconds after disconnecting the plug from its power supply.
For continued protection against fire hazard, replace the line fuse(s) only
with 250 V fuse(s) or the same current rating and type (for example, normal
blow or time delay). Do not use repaired fuses or short circuited
fuseholders.
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