Lead Free

POWER-NIKKOHM

RoHS 2900W
CHASSIS MOUNTING NON-INDUCTIVE
HIGH POWER RESISTORSRPK900Features and Applications
Small size SOT227, 900W high power resistor. Attaching with a large forced air-cooled heat sink or
liquid-cooling would be necessary for high power operation.
Rated power is 900W (single resistor at 25 °C flange temperature), dual resistor configuration is optionallyavailable with 600W (total of dual resistors at 25 °C flange temperature). Please see RPK600.
M4 screw terminals, very low series inductance.
Higher density packing, vibration-proof and perfect heat dissipation are available.
Applications include snubber resistors, breeder resistor, power voltage divider, dumping resistor, brakingresistor for X-ray, MRI, Laser power source and etc.

Schematics

Dimensions
HG
4R1FB

1342

1

RPK900X

CStructure

EDA

R1342

1

RPK900Y

R132

RPK900Z

CaseFilling
Resistor
Terminals
Conductor
ALN substrate
Cu flange, Ni plated

Weight: 36.1grams
Includes terminal screws（M4/6mm）
Symbols
ABCDEFGH(mm)38+/-0.5
25+/-0.5
15+/-0.5
30+/-0.2
15+/-0.5
13+/-0.5
2 – 4.20+/-0.1 dia.
4 - M4.0(inch)
1.50+/-0.02
0.98+/-0.02
0.59+/-0.02
1.18+/-0.008
0.59+/-0.02
0.51+/-0.02
2 - 0.165+/-0.004 dia.
4 - M4.0 (mm)Nikkohm Co., Ltd. 3-31-2640 Minamicho, Misawa, Aomori 033-0036 Japan TEL: +81-176-53-2105, FAX: +81-176-53-2106© Nikkohm Co., Ltd.
URL: http://www.nikkohm.co.jp & http://www.nikkohm.com / e-mail: info@nikkohm.co.jp

Lead Free

POWER-NIKKOHM

RoHS 2900W
CHASSIS MOUNTING NON-INDUCTIVE HIGH POWER RESISTORSRPK900Ordering Information
RPK900|
RPK900

X
C101
J||||
X
C (50ppm)+E24J (5%)
YZ
‘S’ shows supplied terminal screws
Resistance value is available following modified E24, +E24. Another is available optionally.
1.0
1.1
1.2
1.3
1.5
1.6
1.8
2.0
2.2
2.4
3.6
3.9
4.0
4.3
4.7
5.0
5.1
5.6
6.2
6.8

Z03
|
Z03
(RoHS)
Tube pack.
2.5
7.5

2.7
8.0

3.0
8.2

3.3
9.1

Specifications and Performances
Specification Items
Rating Power
Thermal ResistanceResistance Range
Nominal Resistance
TCRTolerance
Operation Temp. Range
Limiting Voltage
Withstanding Voltage
CapacitanceInductanceLoad LifeHumidity

RPK900 X/Y/Z
900 Watts
0.10 °C/W
10 Ω to 1.6KΩ Single
Modified E12+/-50 ppm/°C (C)+/-5% (J)-55 - +155 °C
700V
2500 VAC
13.1 pF
13.7 nH+/-(1.0 %+0.05 Ω)+/-(1.0 %+0.05 Ω)

Temperature Cycle+/-(1.0 %+0.05 Ω)

Short Time Overload
Soldering Heat
Solder ability
Insulation ResistanceVibration+/-(5.0 %+0.05 Ω)---Soldering is not available
Over 1000 meg Ω+/-(0.25 %+0.05 Ω)

140+85 °C

Resistor temperature

1201008080606040+155 °C

200Between terminals and flange.

Resistor temperature °C
160％Rated Power
100Less than E = P ⋅ R
60 seconds. 5000VAC available
Parallel capacitance at 10MHz
Series inductance at 10MHz
25°C, 90min.ON, 30min.OFF, 1000 hours.
70°C, 90 to 95%RH, DC0.1W, 1000 hours.
-55°C, 30 min.,+125°C 30min., 20cycles. (-55°C, 30min.,+120°C, 30min., 5 cycles.)Rating watt×1.5, 5seconds, with heat sink.

Temperature Rise, RPK900

Derating Curve, RPK900
120Conditions
At flange temperature -55 to +85 °C
Between resistor to flange
Not available under 10 ohms.
Any value, option
For -55 to +155 °C
Not available +/- 1% (F) tolerance

40

Flange temperature

200-500+50+100 +150 +200
Flange Temperature (°C)

0200

400 600 800 1000 1200
Application Power (W)Nikkohm Co., Ltd. 3-31-2640 Minamicho, Misawa, Aomori 033-0036 Japan TEL: +81-176-53-2105, FAX: +81-176-53-2106© Nikkohm Co., Ltd.
URL: http://www.nikkohm.co.jp & http://www.nikkohm.com / e-mail: info@nikkohm.co.jp

Lead Free

POWER-NIKKΩRoHS 2900W
CHASSIS MOUNTING NON-INDUCTIVE HIGH POWER RESISTORSRPK900
Pulse Operation

Test Method
DUT
RPK900X-50ohmJ

10,0001,000

Dotted: assumption

Pulse peak power (kW)100
1010.1
0.01
10ns 100ns 1us 10us 100us 1ms 10ms 100ms 1s
Pulse width (duty 0.01)

10s 100s

Above drawing shows allowable pulse peak power that obtained by actual breaking test of RPK900Z-10ohm-J, and shows the result ofdouble safety factor. The test was performed by observation of small resistance change after application of continuous pulse, that isrectangular waveform and 0.01 duty.
Since the pulse durability is moved by the resistance, the pulse waveforms and type of pulse source, constant voltage source or current
source, please test carefully for long terms on actual electronics when operating the resistor by the pulse of the peak power exceeding ratedpower.

DC/AC rms Operation
Resistor generates Joule heat in DC or AC rms
operation at resistor material, and Joule heat shall becooled by thermal conduction. Finally, the heat istransported to the internal air electronics or coolingliquid, makes a steady state. Then, the temperature ofeach portion of a resistor shows a fixed value, as shownin a right figure.
Accumulated heat resistance between resistor material
and air temperature Rt is,
Rt = Rrf + Rfh + Rha
When applied power shows P
Rrf = (tr-tf)/P…°C/W…….0.10°C/W
Rfh = (tf-th)/P..°C/W…….about 0.01°C/W
Rha= (th-ta)/P..°C/W…depends on size of heat sink.
For example:
When Rha=6.0 ° C/W, ta=50 ° C, max resistor
temperature 155 °C and allowable power P1,
P1=(tr-ta)/Rt=(155-50)/(0.1+0.01+6.0)=17.1W
When Rha=0.1 ° C/W, ta=50 ° C, max resistor
temperature 155 °C and allowable power P2,
P2=(tr-ta)/Rt=(155-50)/(0.1+0.01+0.1)=500W

Resistor, resistor temperature, trFlange, flange temperature, tf
Heat sink, heat sink temperature, thAir temperature, ta

Please note, when air cool heat sink is used, actuallykeeping flange at less than 25 °C is difficult. Whenflange temperature is over 25 °C, rating will bedecreased as shown above derating curve.
In DC operation, allowable power depends on a cooling
performance of the heat sink.

Nikkohm Co., Ltd. 3-31-2640 Minamicho, Misawa, Aomori 033-0036 Japan TEL: +81-176-53-2105, FAX: +81-176-53-2106© Nikkohm Co., Ltd.
URL: http://www.nikkohm.co.jp & http://www.nikkohm.com / e-mail: info@nikkohm.co.jp

20201201