Automationdirect.com Stellar SR44, User Manual

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Chapter 1: Mechanical Installation
1.6 – Assisted Flow
An enclosure may need additional fans to maintain the required air temperature immediately
surrounding the unit. This temperature is referred to as the Ambient Temperature. Use the
following formula to determine whether or not fan(s) are required. An allowance has been
incorporated into the formula so that the figure for “Q” should be the air delivery quoted in the fan
supplier’s data.
Q = (4 x Wt) / (t
max
– t
amb
)
• Q = required volume of air in cubic meters per hour (m
3
/h)
• Wt = heat produced by the unit and all other heat sources within the enclosure in Watts (W)
• t
max
= maximum permissible temperature within the enclosure (ºC)
• t
amb
= temperature of the air entering the enclosure (ºC)
(If you prefer to work in CFM, substitute ºF for ºC.)
Refer to the table in section 1.7 for the heat produced by the SR44, and note that the heat figure
(Wt) is the total heat produced by everything within the enclosure.
1.7 – Heat Output of Units
[At rated operational current, I
e
, unit Full Load Current (FLC).]
SR44 Approximate Heat Output (non-bypass)
Chassis Size 1 Chassis Size 2
Model # Heat Output (W) Model # Heat Output (W)
SR44-9
30
SR44-174
520
SR44-16
45
SR44-202
610
SR44-23 60 SR44-242 650
SR44-30 90 SR44-300 850
SR44-44
120
SR44-370
970
SR44-59
155
SR44-72
210
SR44-85 220
SR44-105 275
SR44-146
440
SR44 Series Soft Starter User Manual
1st Ed, Rev B 07/31/2019
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