www.niccomp.com | Technical Support: [email protected] Date: December 15, 2010 Sub: Ripple Current Correction Factors for Aluminum Electrolytic Capacitors The below examples are specific to NRB-XW series products. For correction factors on other NIC product series, please consult NIC product specifications for ripple current correction factor details, or contact NIC to review your requirements [ NIC technical support [email protected] ] Precaution: The combined value of the DC voltage and the peak AC voltage, applied to the component, shall not exceed the rated voltage. Frequency Correction Factor Ripple current correction factor allow use of component under circuit frequencies different than rated specifications NRB-XW series - Ripple Current Frequency Correction Factor The ripple current correction factor table, at left is only applicable to NRB-XW series, and cannot be applied to any other NIC product series Example (Specific to NRB-XW series): Specification: http://www.niccomp.com/catalog/nrbxw.pdf NIC PN: NRB-XW151M450V18x45F Cap = 150uF Voltage Rating = 450VDC RCR = 950mArms @ 120Hz / +105°C Circuit Frequency 60 Hz 120Hz 500Hz 1KHz ≥10KHz Ripple Current Rating (rms) @ +105°C 760mA 950mA 1188mA 1330mA 1425mA Above table shows ripple current ratings for above component NRB-XW151M450V18x45F, when used at circuit frequencies from 60Hz to ≥10KHz From above example, you can safely use NRB-XW151M450V18x45F (150uF / 450VDC) at ripple current of 1.425Arms at circuit frequencies ≥10KHz, with no adverse impact upon load life (endurance) performance. If circuit operation results in component being exposed to ripple current levels exceeding the ratings shown in above table, or under pulse current or pulse voltage conditions, the component may exhibit premature wear-out or failure. Page 1 of 3 Sub: Ripple Current Correction Factors for Aluminum Electrolytic Capacitors The below examples are specific to NRB-XW series products. For correction factors on other NIC product series, please consult NIC product specifications for ripple current correction factor details, or contact NIC to review your requirements [ NIC technical support [email protected] ] Precaution: The combined value of the DC voltage and the peak AC voltage, applied to the component, shall not exceed the rated voltage. Temperature Correction Factor Ripple Current Multipliers allow use of component under current levels higher than rated specifications, with trade-off being reduced load life endurance performance. NRB-XW series - Ripple Current Temperature Correction Factor The ripple current correction factor table, at left is only applicable to NRB-XW series, and cannot be applied to any other NIC product series Example (Specific to NRB-XW series): Specification: http://www.niccomp.com/catalog/nrbxw.pdf NIC PN: NRB-XW151M450V18x45F Cap = 150uF Voltage Rating = 450VDC RCR = 950mArms @ 120Hz / +105°C Load Life Rating = 10,000 hours at +105°C 1.) Operation at +65°C • • • If operating up to 950mA (120Hz) @ +65°C, the load life rating = ~160,000 hrs; >15 years If you opt to use above referenced component under elevated current level, please follow NRBXW ripple current multiplier, as shown in above table. You can safely run the same component at 2.0Arms (950mA x 2.1) = 1995mA, at +65°C, the component can handle the higher current (with higher self heating), but the trade-off is reduction of load life down to 10,000 hours. • 2.) Same conditions apply if operating at +85°C • • • If you opt to use above referenced component under elevated current level, please follow NRBXW ripple current multiplier, as shown in above table. If operating up to 950mA (120Hz) @ +85°C, the load life rating = ~40,000 hours; 4.6 years You can safely run the same components at 1.6A (950mA x 1.7) = 1615mA, the component can handle the higher current (with higher self heating), but the trade-off is reduced load life down to 10,000 hours. Operating Temperature Ripple Current Applied (rms) Load Life (Endurance) Estimation +105°C +85°C +85°C +65°C +65°C 950mA 1615mA 950mA 1995mA 950mA 10,000 hours 10,000 hours ~40,000 hours 10,000 hours >15 years If circuit operation results in component being exposed to ripple current levels exceeding the ratings shown in above table, or under pulse current or pulse voltage conditions, the component may exhibit premature wear-out or failure. Page 2 of 3 Sub: Ripple Current Correction Factors for Aluminum Electrolytic Capacitors Summary: Illustration shows operation zones for (example) +105°C rated aluminum electrolytic capacitor product series, were ripple current correction factors over temperature is shown on product specification. Ripple Current Rating ≤+65°C Ripple Current Rating +105°C Never operate component in red “prohibited operation zone”. If in doubt, please contact NIC to review your requirements: NIC Technical support: [email protected] Prepared by: NIC TPMG Department, NIC Components Corp. Technical support: [email protected] Page 3 of 3