
rev.03/2006A
UT Series
Resistances from 0.005 to 260kOhms
Power Rating 0.1 to 13Watts
Resistance Tolerances to ± 0.01%
Low TCR: ± 20ppm/K Standard
MIL-R-26 / MIL-R-39007 Power Ratings
Temperature Range: -55°C to +350°C ( “V” Rating )
Non-Inductive Windings Available
SPECIFICATIONS
Specification
Tolerances
Temperature Coefficient
Value
±0.01%to±10%(1%Standard)
>10
W
:±20ppm/K
1
W
to10
W
:±50ppm/K
<1
W
:CallFactory
-55°Cto+250°C:CharacteristicU
-55°Cto+350°C:CharacteristicV
500VAC:UT-1/UT-1/2A/UT-1/2/UT-1A
1000VAC:AllOthers
Centerlessgroundceramiccore
Tinnedcopperorcopperweldleads
Hightemperature/trivalent/inorganicSiliconecoating
Allweldedterminations
TemperatureRange
DielectricStrength
Constuction
EnvironmentalPerformance
(MIL-STD202)
D
R
CharacteristicU
±0.2%+0.05
W
±1%+0.05
W
±0.2%+0.05
W
±0.2%+0.05
W
±0.2%+0.05
W
±0.2%+0.05
W
±0.1%+0.05
W
±0.1%+0.05
W
CharacteristicV
±0.2%+0.05
W
±3%+0.05
W
±2%+0.05
W
±2%+0.05
W
±2%+0.05
W
±2%+0.05
W
±0.2%+0.05
W
±0.2%+0.05
W
Dielectric
LoadLife
Storage
MoistureResistance
ThermalShock
5XOverload(5s)
Shock
Vibration
ForNon-InductiveWindings/inserttheletter“N”(i.e.UTN-5)
PartNumber-Resistance-Tolerance-TCR(Ifnotstandard)
Example:UT-525kOhms0.1%
0
50
100
150
200
250
300
350
400
0
20
40
60
80
100
120
P
AmbientTemperature(°C)
CHARU
CHARV
PowerDeratingCurve
SiliconeCoatedPowerResistors
Ordering Information
Willow Technologies Ltd.
Shawlands Court, Newchapel Road, Lingfield, Surrey, RH7 6BL, United Kingdom.
+ 44 (0) 1342 835234
+ 44 (0) 1342 834306
info@willow.co.uk http://www.willow.co.uk