Racal Instruments 1260-X121, Руководство пользователя

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1260-X121 User Manual
Racal Instruments
©
2005 Installation Instructions 2-7
More About
Maximum Current
Ratings
The front panel connector and pins are rated for 10A DC per pin,
with all channels conducting full-rated current. This keeps the
temperature rise within 10
°
C. It should be noted that with all
electromechanical relays, the higher the switched power (voltage
times current), the shorter the useful life of the relays.
Definitions:
•
Max current carrying capacity
The maximum current that the relay can conduct if the relay is
not switched while voltage is applied. The maximum current
carrying capacity is affected by the size of the conducting
section of the contact at its smallest area. The listed values are
obtained from several tests in laboratories under room-
temperature conditions (21
°
C). The contact is considered to be
in free air. The maximum current carrying for the 1260-X121 is
10 A.
•
Max o perating current
The current the contacts can switch while conducting, without
deteriorating. This depends on working conditions, such as
dissipated heat, cooling provisions, ambient temperature,
insulation material, etc. The maximum operating current for the
1260-X121 is 10 A.
•
Recommended continuous current
The maximum current recommended for indefinitely-long time
periods. The primary concern here is the heat generated in the
relay. This specification can be applied for normal working
conditions. The specification includes a safety margin. However,
there are restrictions in the application of the given values. The
most important restriction is the cross-sectional area of the
connecting wire, insulation temperature range, and wire
bundling. The recommended continuous current for the 1260-
X121 is 10 A.