Pulse width modulated battery charging & Ipads etc

[Dafydd Llewellyn]

The interesting article in the latest RAA magazine on the implications of pulse width battery charging control (as used with the permenent-magnet alternators on Jabiru and Rotax engines) leads me to wonder whether the voltage spikes that the article shows, would present a hazard to things like a mini-Ipad or BadElf GPS, if these are supplied with power from the aircraft system, via the typical 12V DC regulators, which are presumably designed for motor vehicles that have field-current voltage regulation. The article points out that one should stick to lead/acid battery types with permanent-magnet alternators using pulse-width charging control; and presumably these will greatly reduce the voltage spike amplitude reaching the aircraft's system, however the lithium batteries in some of these devices may not tolerate being fed that sort of diet. Can anybody supply information on this point?

 

 

[frank marriott]

Haven't got mag yet but considering the supply for iPad for example is via a 4.5v solid state regulator after ships supply I would expect this should remove any spikes.

 

I know of a few being powered this way without trouble, at least so for anyway. Others may have a different opinion.

 

 

[jetjr]

I have significant rf interfereance from ipad charger

 

Cant find better than std retail ciggy charge adapters either

 

 

[frank marriott]

I have significant rf interfereance from ipad chargerCant find better than std retail ciggy charge adapters either

A mate had RFI with a cheap cigarette adaptor but not with a dearer one - 3 & 10 dollars units. I don't know what they are using for a voltage regulator as they are sealed.

 

I haven't used mine in the aircraft yet, as I only carry it as a back up pwr supply and currently get over 5 hours from the internal battery on the Ipad and 5 hrs in one leg is long enough for me