User guide

www.vishay.com For technical questions, contact: [e-mail] Document Number: 50005
16 Revision: 24-Nov-08
RTO 20
Vishay Sfernice
Power Resistors, Thick Film Technology
OVERLOADS
In any case the applied voltage must be lower than the
maximum overload voltage of 375 V.
The values indicated on the graph below are applicable to
resistors in air or mounted onto a heatsink.
MARKING
Model, style, resistance value (in Ω), tolerance (in %),
manufacturing date, VISHAY trademark.
POWER RATING CHART
The temperature of the heatsink should be maintained within
the limits specified.
To improve the thermal conductivity, surfaces in contact
should be coated with a silicone grease and the torque
applied on the screw for tightening should be around 1 Nm.
Spring clip can also be used to mount the component on an
heatsink (ex: Kunze, clip KU4-498).
10
-6
ENERGY IN JOULES
OVERLOAD DURATION IN S
ENERGY CURVE
0.01
0.1
1
10
10
-5
10
-4
10
-3
10
-2
10
-1
10
-7
100
PACKAGING
Tube of 50 units
0
100
75
50
25
0
% RATED POWER
HEATSINK TEMPERATURE IN °C
20
40
60
80
100
120
140 155
120
ORDERING INFORMATION
RTO 20 F U68 5 % xxx TU50 e3
MODEL STYLE CONNECTIONS RESISTANCE VALUE TOLERANCE CUSTOM DESIGN PACKAGING LEAD (Pb)-FREE
F: Radial leads
C: Surface mount
± 1 %
± 2 %
± 5 %
± 10 %
Optional
on request:
special TCR,
shape etc.
GLOBAL PART NUMBER INFORMATION
GLOBAL
MODEL
SIZE LEADS OHMIC VALUE TOLERANCE PACKAGING
RTO 020 F = Radial leads
C = Surface mount
The firts four digits are
significant figures and the last
digit specifies the number of
zeros to follow.
R designates decimal point.
48R70 = 48.7 Ω
48701 = 48 700 Ω
10002 = 100 000 Ω
R0100 = 0.01 Ω
R6800 = 0.68 Ω
27000 = 2700 Ω = 2K7 Ω
F = 1 %
G = 2 %
J = 5 %
K = 10 %
T = Tube
Size 30 and 50:
Tube 50 pieces
020FR68 0T3T OR 0JE