NPR NPP
2-T126
TO-126 Power Film Resistors
SPECIFICATIONS
(continued)
Power Derating Curve
120
100
Power Rating Notes -
The NPR 2-T126 Series Foil Resistors must be attached to a
suitable heatsink. The maximum internal resistor temperature is
155°C (120°C for the NPP 2-T126).
To specify an appropriate heatsink use the following formula :
Power ( % )
80
60
40
20
0
NP
NP
P
2
-T
12
R
2-T
12
6
6
R
qH
= T
MAX
- ( P x R
qR
) - T
A
P
125
150
175
-25
0
25
50
75
100
Ambient Temperature (°C)
Where:
R
qH
= Thermal Resistance of Heatsink ( K/W )
R
qR
= Thermal Resistance of Resistor ( K/W )
T
MAX
= Maximum Temperature of Resistor
T
A
= Ambient Temperature of Heatsink ( °C )
P = Power Through Resistor ( W )
Mounting Notes -
The NPR 2-T126 Series Film Resistors must be attached to
a suitable heatsink. Mount resistor using thermal grease to
a clean / flat surface. Use a compression washer to provide
150 to 300 pounds ( 665 to 1330N ) of mounting force. Torque
mounting screw to 8 in-lbs ( 0.9 Nm ).
Ordering Information
Part Number - Resistance - Tolerance - TCR
Example: NPR 2-T126 0.5 Ohm 1% 100ppm
Riedon Inc.
1.01
300 Cypress Avenue
Alhambra CA 91801
(626) 284-9901
(626) 284-1704
Page 79
RIEDON [ RIEDON POWERTRON ]
