13 Calculating the power dissipation
ESR5-NV3-300
12/19 MN049006EN
www.eaton.com
19
13 Calculating the power dissipation
Input power dissipation
P
Input
=
U
B
²
/
(U
N
/I
N
)
Contact power dissipation
With the same load currents:
P
Contact
=
n
x
I
L
²
x
200
m
Ω
With different load currents:
P
Contact
=
(I
L1
²
+
I
L2
²
+
…
+
I
Ln
²
)
x
200
m
Ω
Total power dissipation
P
Total
=
P
Input
+
P
Contact
therefore
P
Total
=
U
B
²
/
(U
N
/I
N
)
+
n
x
I
L
²
x
200
m
Ω
or
P
Total
=
U
B
²
/
(U
N
/I
N
)
+
(I
L1
²
+
I
L2
²
+
…
+
I
Ln
²
)
x
200
m
￫
The total power dissipation of the safety relay is based on the
input power dissipation and the contact power dissipation for
the same and for different load currents.
P
Power dissipation in mW
U
B
Applied operating voltage
U
N
Nominal input voltage
I
N
Input current
n
Number of enabling current paths used
I
L
Contact load current
Summary of Contents for 171858
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