Rev Date: 10/22/2020

2

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This specification may be changed at any time without prior notice.

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Please confirm technical specifications before you order and/or use.

RSPF / RSPL Series

Flameproof Power Resistor

Stackpole Electronics, Inc.

Resistive Product Solutions

Power Derating Curve:

Repetitive Pulse Information:

If repetitive pulses are applied to resistors, pulse wave form must be less than “pulse limiting voltage”, “pulse limiting

current” or “pulse limiting wattage” calculated by the formula below.

Where: Vp:

Pulse limiting voltage (V)

lp:

Pulse limiting current (A)

Pp:

Pulse limiting wattage (W)

P:

Power rating (W)

R:

Nominal resistance (ohm)

T:

Repetitive period (sec)

t:

Pulse duration (sec)

K:

Coefficient: 0.9

[Vr:

Rated Voltage (V), Ir: Rated Current (A)]

Note 1:

If T > 10 → T = 10 (sec), T / t > 1000 → T / t = 1000

Note 2:

If T > 10 and T / t > 1000, “Pulse Limiting power (Single pulse) is applied

Note 3:

If Vp < Vr (lp < lr or Pp < P), Vr (lr, P) is Vp (lp, Pp)

Note 4:

Pulse limiting voltage (current, wattage) is applied at less than rated ambient temperature.

If ambient temperature is more than the rated temperature (70°C), decrease power rating according to “Power

Derating Curve”

Note 5:

Assure sufficient margin for use period and conditions for “pulse limiting voltage”

Note 6:

If the pulse waveform is not square wave, judge after transform the waveform into square

wave according to the “Waveform Transformation to Square Wave”.

Performance Characteristics

Test

Test Results

Short Time Overload

± (0.75% + 0.05Ω)

Moisture Resistance

± (5% + 0.05Ω)

Load Life @ 70ºC - 1000 hours

± (5% + 0.05Ω)

Dielectric Withstanding Voltage

± (5% + 0.05Ω)

Resistance to Solvent

Permanent marking no physical damage or deterioration

Operating temperature range is -55ºC to +155ºC

Vp =

K√P x R x T/t

lp =

K√P/R x T/t

Pp = K

2 x P x T/t