NCC铝电解电容器寿命计算方法

TO : PI Electronics HK

Life Estimation Formula

ÑFor Input Filtering (ripple frequency 100 - 120Hz) :

160V or Higher Rated Voltage

Available to apply KMG, KMH, KMM, KMQ, SMH, SMM, SMQ and some

other series for input filtering .........................................................................…........... Page 2 - 4ÑFor Output Filtering (ripple frequency 10k - 100kHz) :

Low-ESR Radial Type Capacitors up to 100V Rated Voltage

Available to apply KY, KZE and KZH series for output filtering ................................… Page 5

Available to apply LXJ, LXV, LXY, LXZ, KMY series for output filtering.................... Page 6 - 8ÑFor Snap-ins and 105o C Radial up to 100V rated items ..................................... Page 9

Available to apply KMH and SMH series for Snap-ins

Available to apply KMQ, KMG, KME, KMF series for 105o C Radial

ÑFor other types, general use capacitors .............................................................. Page 10

Available to apply Chip, 5mm height, 7mm height, Other Radial

ÑAppendix ..................................................................................................................... Page 11, 12

Nippon Chemi-Con Corporation

Revised May03, 2004

HCC Engineering

Koh Ohno

May . 03

, 2004

Life Estimation Formula for the Capacitors of

160 volts or Higher Rated Voltage

When a ripple current frequency is 100 - 120Hz,

i. When ∆Tx 20o C,

Lx

= Lo x

2

(To – Tx)/10

x 2

(∆To – ∆Tx)/8

x (Vo / Vx)4.4 (1)

Where: Lx = Lifetime (hours) of the capacitor to be estimated Lo = Base (Assured) lifetime (hours) of the capacitor

To = Maximum rated operating temperature (o

C)

Tx = Actual ambient temperature (o

C) of the capacitor within device (This is not the environment tempe- rature of the device, but the environment tempera- ture of the capacitor that has been placed within the device.)

∆To = Rise (o

C) in core temperature of the capacitor due to rated (permissible) maximum ripple current. The ∆To values designed for the KMH capacitors is

5o

C maximum.

105o C type capacitors: 5o

C max.

85o C type capacitors: 10o

C max.

∆Tx = Actual rise (o

C) in the core temperature of the capacitor due to actual ripple current at device operating conditions. To calculate the ∆Tx from the surface temperature of the capacitors, refer to the appendix 1. Also, to simply estimate the ∆Tx from the actual rms ripple current, use the following equation: ∆Tx = ∆To x [ (actual rms ripple) / (rated rms ripple) ]^2 The actual and rated maximum rms ripple current shall be

equaled in frequency by using frequency multipliers prescribed for each product series in the catalog.

Vo = Rated voltage (V) of the capacitor

Vx = Actual operating voltage (V) which is applied to the capacitor at the device. When the actual operating voltage (Vx ) is less than 80% of the rated voltage (Vo), the actual operating voltage (Vx) in the

formula (1) shall be considered as 80% of the Vo.