Configuration instructions
3.4 Installation altitude and ambient temperature
3RW44 soft starters
26
Manual, 03/2017, NEB535219502000/RS-AB/008
3.4
Installation altitude and ambient temperature
The permissible installation altitude must not exceed 5000 m above sea level (above 5000 m
on request).
If the installation altitude exceeds 1000 m, the rated operational current must be reduced for
thermal reasons.
If the installation altitude exceeds 2000 m, the rated voltage must also be reduced owing to
the limited dielectric strength. A maximum permissible rated voltage of ≤ 460 V applies at
installation altitudes between 2000 m and 5000 m above sea level.
The following diagram shows the reduction in the rated device current as a function of the
installation altitude:
The rated operational current I
e
must be reduced at altitudes higher than 1000 m above sea
level.
Figure 3-2
Reduction as a function of the installation altitude
Ambient temperature
3RW44 soft starters are designed for operation with rated current at an ambient temperature
of 40 °C. If this temperature is exceeded, e.g. owing to an impermissible temperature rise in
the control cabinet, other loads, or a general increase in the ambient temperature, the
resulting deterioration in the soft starter's performance must be taken into account when the
device is dimensioned (refer to chapter Technical data of the power unit (Page 259)).
