RPS500 VISHAY [Vishay Siliconix], RPS500 Datasheet - Page 2

• Manufacturer Part Number: RPS500
• Description: Power Resistors for Mounting onto a Heatsink Thick Film Technology
• Manufacturer: VISHAY [Vishay Siliconix]

Document Number: 50047
Revision 14-Jan-04
CHOICE OF THE HEATSINK
The user must choose the heatsink according to the working conditions of the component (power, room temperature).
Maximum working temperature must not exceed 125°C.
The dissipated power is simply calculated by the following ratio:
RECOMMENDATIONS FOR MOUNTING ONTO A HEATSINK
Surfaces in contact must be carefully cleaned.
The heater must have an acceptable flatness: from 0.05mm to 0.1mm/100mm.
Roughness of the heatsink must be around 6.3µm.
In order to improve thermal conductivity, surfaces in contact (alumina, heatsink) should be coated with a silicon grease (type
SI 340 Rhône-Poulenc or Dow Corning).
The fastening of the resistor to the heatsink is under pressure control of two screws. Tightening torque: 4Nm.
The following accessories are supplied with each product: 2 off M 4 x 16, 2 off M4 TE 4 x 0.6 and 2 off M4 washers.
PERFORMANCE
TESTS
Momentary Overload
Rapid Temperature Change
Load Life (chassis mounted)
Humidity (steady state)
RESISTANCE VALUE IN RELATION TO TOLERANCE AND TCR
Ohmic
Standard Tolerance
Standard T.C.R.
Tolerance On Request
P:
∆T:
R
R
TH:
TH:
expressed in W
difference between maximum working temperature and room temperature.
(j-c): thermal resistance value measured between resistive layer and outer side of the resistor. It is the thermal
resistance of the component: 0.11°C/W.
(c-a): thermal resistance value measured between outer side of the resistor and room temperature. It is the
thermal resistance of the heatsink, depending on the heatsink itself (type, shape) and the quality of the fastening
device.
Power Resistors for Mounting onto a Heatsink
For technical questions, contact [e-mail]
± 300ppm/°C
1000 hours 500 W/70°C (no cycling)
MIL STD 202 Method 103 B and D
NF EN 140000 CEI 68214 Test Na
P =
± 5%
< 1Ω
Thick Film Technology
5 cycles - 55°C to + 125°C
NF EN 140000 CEI 115_1
NF EN 140000 CEI 115_1
[R
TH
56 days 95% R.H.
2Pn/10 seconds
(j-c) + R
CONDITIONS
∆T
TH
± 1% - ± 2% - ± 10%
(c-a)]
(1)
± 150ppm/°C
± 5%
> 1Ω
< ± (0.25% + 0.05Ω)
< ± (0.25% + 0.05Ω)
< ± (0.5% + 0.05Ω)
< ± (0.5% + 0.05Ω)
TYPICAL DRIFTS
Vishay Sfernice
RPS 500
www.vishay.com
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