On 8 Nov 2005 at 12:51, Toralf Lund wrote: > Leon Altoff wrote: > > > Hi, > > > > The R-CRV-3 batteries are not recommended for use in the Pentax > > cameras. They supply too high a current that can cause motors to burn > > out. > > > I'm not sure I understand how that can happen. Aren't batteries voltage > sources, not current sources?
These cells rely upon a higher initial and average voltage to achieve an acceptable run time (until the camera deems that the voltage is too low to operate) even though they hold a lower total charge. A battery is a complex device, it can loosely be considered as a voltage source (with unlimited current) in series with a resistance (an internal dynamic resistance which varies dependent upon load current). Current and hence power in the a linear circuit increases as voltage rises for a constant load, it's ohms law. Being that the terminal voltage is higher than the normal battery voltage there may be potential for damage of the camera electronics. I assume that the cameras in question employ electronic power supply regulation, if so these circuits could potentially be stressed or damaged by an over voltage battery supply. Care to test the theory? Given the high cost of CRV3 rechargeable batteries, non-uniformity of systems and specialized chargers required I really don't see why it would be worth the effort. Also I'm not aware of their self discharge rate either but from practical experience with other L-ion powered devices they aren't my favourite batteries in this regard. Cheers, Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://members.ozemail.com.au/~distudio/publications/ Pentax user since 1986, PDMLer since 1998
