Answer3

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	WHAT'S YOUR ENGINEERING QUOTIENT?
•Take a Swing! Problem 3—Out of lead acid, NiCd, and NiMH battery chemistries, which one is not suitable for on-line power-fail backup applications? Answer: Despite the energy density and lack of memory effect, NiMH cells cannot be trickle charged. This makes NiMH unsuited to on-line power-fail backup. NiCd cells can be trickle charged by constant current and lead-acid cells can be trickle charged by constant voltage. NiCd and lead-acid are both suitable for on-line power-fail backup given a proper trickle charger is present. 1-00 For questions or comments about Test Your EQ, e-mail eq@circuitcellar.com.