Advanced Measurement Technology 273A, Руководство пользователя

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Warning! If it is necessary to replace the power cord or the power cord plug, the replacement
cord or plug must have the same polarity as the original. Otherwise a safety hazard
from electrical shock, which could result in personnel injury or death, might result.
Fig. 1. Power Cord Plug with Polarity Indication.
2. SAFETY CONSIDERATIONS
2.1. Introduction
The apparatus to which this instruction manual applies has been supplied in a safe condition.
This manual contains some information and warnings that have to be followed by the user to
ensure safe operation and to retain the apparatus in a safe condition. The described apparatus
has been designed for indoor use.
2.2. Safety Mechanism
As defined in EEC Publication 348, Safety Requirements for Electronic Measuring Apparatus, the
Model 273A is Class I apparatus, that is, apparatus that depends on connection to a protective
conductor to earth ground for equipment and operator safety. Before any other connection is
made to the apparatus, the protective earth terminal must be connected to a protective conductor.
The protective connection is made via the earth ground prong of the Model 273A's power cord
plug. This plug shall only be inserted into a socket outlet provided with the required earth ground
contact. The protective action must not be negated by the use of an extension cord without a
protective conductor, by use of an adapter that doesn't maintain earth ground continuity, or by
any other means.
The power cord plug provided is of the type illustrated in Fig. 1. If this plug is not compatible with
the available power sockets, the plug or the power cord should be replaced with an approved
type of compatible design.
In many parts of the world, commonly used power plugs and sockets differ from those in general
use in the United States. For this reason, cords supplied with units to be used outside the United
States may not be furnished with a power plug, making it necessary for the user to obtain and
install a power cord plug suited to use in their area.
For safety, it is necessary that normal polarity relationships be maintained. The wires in the
supplied power cord are color-coded for this purpose. Whatever the actual plug configuration,
the black wire should be the line or active conductor (also called "live" or "hot"), the white wire
should be neutral, and the green wire should be earth ground.
2.3. Power Voltage Selection and Line Fuses
Before plugging in the power cord, make sure that the equipment is set to the voltage of the ac
power supply.