Hꢀgh eꢁꢂrgy Wꢀrꢂwꢃuꢁd
Axial Terminal / Surface Mount / Heat Sinkable Packaging
Ohmite Manufacturing’s family of High Energy
Wirewound Resistors employ special winding tech-
niques to maximize the effective joule rating of each
resistor. Most wirewound resistors are wound with
the objective of meeting the stated power (watt-
age) rating and keeping cost low through the use
of automatic winding equipment. Typically, manu-
facturers will allow substitution of resistance wire,
depending on material availability. On tight tolerance
wirewounds some type of abrasive adjustment to the
resistance wire is often used to maximize production
yields. Both of these procedures can adversely affect
the joule rating and fusing current of a wirewound
resistor, and this is often the reason that the manu-
facturer does not publish a fixed joule rating.
Ohmite High Energy Wirewounds are wound so
as to maintain the tightest possible pitch (space
between windings) and thereby maximize the mass
of the resistive element. Since no wire substitutions
are allowed, and no abrasive adjusting is permitted
in this family, Ohmite can publish a fixed joule rat-
ing and fusing current for each part number in the
series.
This technique can be applied to any wirewound
product. In order to provide the broadest selection of
packaging, Ohmite has developed standard offerings
in three different package types-axial, SMD, and heat
sinkable. Other sizes and types can be quoted on
request, such as tubular power resistors.
seRies sPeCiFiCATions
Series
33Jxxx
Type
Axial
Watts
3
Tolerance
5%
Voltage
200
35Jxxx
30Jxxx
825JxxxH
RH3R0DBxxxJ
Axial
Axial
Heat Sinkable
Surface Mount
5
10
25
3
5%
5%
5%
5%
460
1000
520
200
Dimensions
825JxxxH: 1.938 / 49.23
33J: 0.593 / 15.1
35J: 1.000 / 25.4
30J: 1.900 / 46.8
0.546 / 13.87
in. / mm
1.5 / 38.1
33J: 0.218 / 5.5
35J: 0.343 / 8.7
30J: 0.406 / 10.3
33J: 20 ga.
35J: 18 ga.
30J: 18 ga.
RH3R0DBxxxJ: 0.612 / 15.545
0.273 / 6.934
1-866-9-OHMITE • Int’l 1-847-258-0300 • Fax 1-847-574-7522 • www.ohmite.com • info@ohmite.com
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