Power dissipation – Rockwell Automation 1398-DDM-xxx USE MNL/ULTRA 200 DIG.SERVO.DR User Manual
Page 297

Publication 1398-5.0 – October 1998
Specifications
G-7
Power Dissipation
The ULTRA 200 Series controller dissipates power that results in
cabinet heating. The following table lists power dissipation values for
the ULTRA 200 Series drives. Calculate the cabinet cooling
requirements using the power dissipation information and formulas
below.
Maximum power losses are shown to help size a NEMA 12 or
equivalent enclosure and to ensure the required ventilation. Typical
power losses are about one-half maximum power losses.
When sizing an enclosure with no active method of heat dissipation,
the following equation approximates the size of enclosure necessary:
T
F
= 4.08 * (Q/A) + 1.1
or
T
C
= 2.27 * (Q/A) + 0.61
where:
T
F
= Temperature difference between inside air and outside
ambient (
°
F)
T
C
= Temperature difference between inside air and outside
ambient (
°
C)
Q = Heat generated in enclosure (watts)
A = Enclosure surface area in ft
2
= (2dw + 2dh + 2wh) / 144
d = Depth in inches
h = Height in inches
w = Width in inches
Current as % of
Rated Continuous
Current
1398-DDM-
010,
1398-DDM-
010X
1398-DDM-
020,
1398-DDM-
020X
1398-DDM-
030,
1398-DDM-
030X
1398-DDM-
075,
1398-DDM-
075X
1398-DDM-
150,
1398-DDM-
150X
100
75 W
100 W
150W
300 W
500 W
NOTE:
These values do not include internal or external shunt regulator power (regenerated power).
Refer to “TB2 – Shunt Regulator” on page 7-11 for shunt regulator dissipation values.