An analogy
Hi,
The (negative going) voltage spikes in the bus is similar to:
Imagine a large piston engine (mechanically) connected by a rod to a flyweel. The stress to the connection could destroy the rod. The diode could be viewed as "part of the rod". And the series connected cells must be capable to supply the large current spikes. The spikes could concentrate in some (area) concentrated points during the transient? And all these current spikes could even create oscillatory voltage transients increasing momentarily cell voltages above nominal levels?
The low MTTR reported probably was on MAIN batteries for other reasons. (supposing very rare use of APU battery discharging high current. And during towing the load is light. )
Last edited by RR_NDB; 31st Jan 2013 at 18:18.
Reason: Typo