Rev Date: 06/30/2021

5

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

ASR / ASRM Series

Anti-Surge Resistor

Stackpole Electronics, Inc.

Resistive Product Solutions

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: 1

[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), please decrease power rating according to “Power

Derating Curve”.

Note 5:

Please assure sufficient margin for use period and conditions for “Pulse limiting voltage”.

Note 6:

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

according to “Waveform Transformation to Square Wave” information.

Vp = K√P x R x T/t

lp = K√P/R x T/t

Pp = K

2 x P x T/t