Master Switch

On Thursday, October 17, 2013 9:10:25 AM UTC-5, Dan Marotta wrote:

Or I could simply divide my equipment across two (or three) busses and then

rely on the load division to allow the batteries to last an entire flight.

Dan, that's how I've had my LS6 setup for over 13 years and it has worked just fine so far.

2 separate busses, one for each battery, with load divided as equally and logically as possible (split varios and loggers, for example).

In addition, the master switch for each buss can also select either battery, so if one battery fails (forgot to charge it?) the essential instruments can be powered by the remaining battery.

Probably WAY over-engineered, but it was fun to wire up and has worked as designed so far (ugly to look at, though - bit of a spaghetti factory behind that small LS6 panel that I want to clean up some day...).

Kirk
66

How about this, diagram below.
Each battery should have its own fuse.
Switches are drawn as -o\-
Vertical line is the Master bus.
Optional PV charge controller charges the active battery, whether avionics are on or off.
I'd suggest locking switches like Alcoswitch MTL106D available from Mouser for $12.60.
Jim

Bat 1 -----o\-----|
Bat 2 -----o\-----|
Bat 3 -----o\-----|
|-----o\----- Avionics
PV Charger -------|

Sorry, the line looked vertical before shipping.
Jim

On Wednesday, October 23, 2013 2:34:15 PM UTC-4, JS wrote:
Sorry, the line looked vertical before shipping.

Jim

I would put a fuse downstream of the PV charger. If it develops a short, your whole system dies.

Right you are, Flub.
As well as the individual loads.
Jim

On Wednesday, October 23, 2013 5:10:37 PM UTC-7, son_of_flubber wrote:

I would put a fuse downstream of the PV charger. If it develops a short, your whole system dies.

Those switches look like what I used as my new master switch, except mine is
DPDT. I could use one to power two separate busses from two separate
batteries.


"JS" wrote in message
...
How about this, diagram below.
Each battery should have its own fuse.
Switches are drawn as -o\-
Vertical line is the Master bus.
Optional PV charge controller charges the active battery, whether avionics
are on or off.
I'd suggest locking switches like Alcoswitch MTL106D available from Mouser
for $12.60.
Jim

Bat 1 -----o\-----|
Bat 2 -----o\-----|
Bat 3 -----o\-----|
|-----o\----- Avionics
PV Charger -------|

In article JS writes:
How about this, diagram below.
Each battery should have its own fuse.
Switches are drawn as -o\-
Vertical line is the Master bus.
Optional PV charge controller charges the active battery, whether avionics are on or off.
I'd suggest locking switches like Alcoswitch MTL106D available from Mouser for $12.60.
Jim

Bat 1 -----o\-----|
Bat 2 -----o\-----|
Bat 3 -----o\-----|
|-----o\----- Avionics
PV Charger -------|

I would seriously recommend against this.

If you only turn on the avionic load switch, with no batteries in
the circuit, the avionics will see the full open circuit output of
the solar panel.

Many "12 volt" panels deliver in the vicinity of 21.6 volts open
circuit -- even if not that high, they can easily be enough to damage
electronics.

Charge should be applied through a charge controller, so the panel
doesn't overcharge and cook the battery, and should be applied in
such a way that it cannot be applied directly to the load alone.

Alan

If anyone is interested my panel wiring can be found he

www.boffins.co.uk/downloads/j1mwiring.pdf

Jim

Very nice, Jim. I'm going to save a copy of that!


"Jim White" wrote in message
...
If anyone is interested my panel wiring can be found he

www.boffins.co.uk/downloads/j1mwiring.pdf

Jim

Sorry to confuse.
There's a Strobl OS2H charge controller on the glider installations:
"Optional PV Charge Controller" Abbreviated like the fuses and connectors are in the text-only drawing.
Jim

On Wednesday, October 23, 2013 10:55:06 PM UTC-7, Alan wrote:
In article JS writes:

How about this, diagram below.

Each battery should have its own fuse.

Switches are drawn as -o\-

Vertical line is the Master bus.

Optional PV charge controller charges the active battery, whether avionics are on or off.

I'd suggest locking switches like Alcoswitch MTL106D available from Mouser for $12.60.

Jim



Bat 1 -----o\-----|

Bat 2 -----o\-----|

Bat 3 -----o\-----|

|-----o\----- Avionics

PV Charger -------|



I would seriously recommend against this.



If you only turn on the avionic load switch, with no batteries in

the circuit, the avionics will see the full open circuit output of

the solar panel.



Many "12 volt" panels deliver in the vicinity of 21.6 volts open

circuit -- even if not that high, they can easily be enough to damage

electronics.



Charge should be applied through a charge controller, so the panel

doesn't overcharge and cook the battery, and should be applied in

such a way that it cannot be applied directly to the load alone.



Alan