4
SR35 Quick-Start Guide
Stellar® SR35 Series Soft Starter Quick Start Guide – 1st Ed – 07/09/2020
Mechanical Installation
m
ounTIng
Fix the unit to a flat, vertical surface using the mounting holes (or slots) on its
base-plate. The mechanical outline diagrams, shown on
, give the
dimensions and mounting hole positions for each model. Ensure that:
•
The orientation of the unit has the ‘TOP’ uppermost
•
The location allows adequate front access
•
You can view the keypad display
•
Do not install other equipment that generates significant heat close to the soft
starter
r
equIremenTs
for
an
e
nClosure
For a typical industrial environment, an enclosure would provide the following:
•
A single location for the unit and its protection/isolation switch-gear
•
The safe termination of cabling and/or busbars
•
Means to effect proper air flow through the enclosure if the heat output of the unit is
greater than the cabinet can dissipate
e
nClosure
V
enTIlaTIon
When installing the SR35 soft starter into a cabinet, ventilation must be provided
if the heat output of the unit is greater than the cabinet can dissipate. The heat
dissipated can be approximated with the formula:
•
Starting: Watts (SR35) =
(start current(A)) x (start time(s)) x (number of starts per hour) ÷ 1800
•
Running: Watts (SR35) = 04 x running amps
Use the following formula to determine the fan requirement. An allowance has been
incorporated into the formula so that the figure for Q is the air delivery in the fan
suppliers’ data.
•
Q = (4 x W
t
) ÷ (T
max
- T
amb
)
•
Q = Volume of air (cubic meters per hour - m
3
/h)
•
W
t
=
Heat produced by the unit and all other heat sources within the enclosure (Watts)
•
T
max
= Maximum permissible temperature within the enclosure
(40°C for a fully rated SR35)
•
T
amb
= Temperature of the air entering the enclosure (°C)
(If you prefer to work in CFM, substitute °F for °C Q is now in CFM)
a
lTITude
d
eraTe
Altitude above sea level 1000m (3281ft).
Above 1000m, derate by 1% of SR35 i.e. per 100m (328ft) to a maximum altitude of
2000m (6562ft).
a
mbIenT
T
emperaTure
d
eraTe
-20°C (-4°F) to 40°C (104°F).
Above 40°C, derate linearly by 2% of SR35 i.e. per °C to a maximum of 60°C (140°F).
