Hmmmmm...... Maybe this is just for LNC2's.

 

I have used the B&C, model # BC110-1 for years (these are Odyssey-like).  One of the original ones from the late nineties is still in use on a generator with an electric starter.  I have several still good ones lying around since I put a new one in every three or four years. Here's how it all works for me. 

 

I soon reached high electrical system reliability by using a B&C starter, generator, voltage regulator and battery after, uh, experimentation with a mix of components. I have a Nuckoll's essential bus system and a dual LSI ignition where one is powered off the main bus and one off the essential with a 5 AH battery backup exclusively switchable for one of the ignitions.  If I am not going to fly for a while, I hook up a Battery Tender to the main through a power plug in the glove box.

 

The final preflight is to switch on the essential bus to bring up the engine monitor with its volt meter, turn on the ignition backup battery (it powers only the ignition on the now dead main bus) and switch the voltmeter to read that back up battery level.  Since the only load is the single ignition box, the reading should be 13.1 VDC and if not, get out of the plane and find out why.  The voltmeter is then switched to read the essential bus voltage direct from the main battery and that should be 12.7 VDC since that bus is carrying some load from various things on the bus.  If the reading is lower, get out and investigate.  The important thing is that there should be no variance since the plane was just pulled from its heated hangar. If all is OK, on goes the master switch and off with the others.  Note: The voltmeter is also be used to read the main bus voltage in flight so that the electrical system can be monitored for the approximate 14.3 VDC as controlled by the regulator and the essential bus checks in at about 13.9 due to the drop across the isolation diode. The backup battery is also being charged through its isolation diode during flight.

 

Experience has shown that storing the airplane with the master switch on will cause the battery to drain until the master relay can no longer be held in.  It is possible to recover from this with a Battery Tender that has a facility to restore the plate condition in the battery.  If the essential bus (direct to battery) switch was left on, the battery will be drained to zero and its future is suspect since recovery may not be possible - replace it. 

 

Also, a normal battery charger can be used if it is monitored - it may not stop at 14.3 volts and may destroy the battery after nearing 15+ volts.  Never leave an automobile charger on a battery when unattended (like overnight). 

 

It is shocking to be jolted by an electrical failure in any modern airplane without some early warning (voltage out of range, generator out, high discharge, etc.).

 

Blue Skies and electron movement,

 

Grayhawk