Basic Not black & white but I would say the TV would also draw lots of power too (fast)
to last long which isn't mentioned.
Then why not also split the batteries positive (red) lead away from each other once settled
and all the driving charge is then completed (remember to connect them back together(small spark) (whilst not running engine as a huge spark when touching connection back on. So when moving away to charge the separated
battery once again. But run the sat box from the separated
battery and use the
solar to charge that one only (keep an eye on voltage (use a meter)to no less that 11.7 volts on either)
(You can work out power using this equation: P(P is the power in watts) = I × V. , W. I is the current in amperes (amps), A. V is the potential differences in volts, V.
I
___________
V X W Watts
so to work out Amps
I(current)
=
V X W Watts
12 x 0.3
300watt
inverter will (on average use) but a
battery loses voltage as well as it goes along,
The simple answer is- divide the load watts by 10. E.g. For a load of 300 Watts, the current drawn from the
battery would be:
300 (w)÷ 12 (v)= 25 Amps(I) (quite a large draw)
Also characteristics of a leisure
battery works different to a led acid so does NiCad dry cell etc etc ...
• For a more accurate calculation of
battery current: Divide load watts by actual
battery voltage, this will be in the range 12-14V.
Then to allow for
inverter efficiency, typically 85%, divide the figure by 0.85. Thus:
For a 300W load at 12V....300 ÷ 12 ÷ 0.85 = 29.4 Amps.
(and between fully charged)
For a 300W load at 14V....300 ÷ 14 ÷ 0.85 = 25.2 Amps.
You can see the simple divide by 10 gives an easy estimated "worst case" guide.
Notes:
• It is the actual load watts drawn, not the
inverter rating that counts as the load drwn will change with the units you use. So a 1500W
inverter with a 500 Watt load would be 50 Amps, not 150 Amps.The same
inverter with a 1200 Watt load would draw 120 Amps.
• For a quick idea of how long a
battery will last without the alternator running (but with the trickle charge of the
solar not included),
How long will my
battery last with an
inverter load is impossible to estimate also really, no one can give you a definitive answer without all the facts
SO answer
(read a book)no sorry
The other free sat receiver shouldn't be too bad if you could use a directly connected 12 V DC free sat /recorder receiver to 12v DC which would be far superior and far less draw.
As it wont be transforming power then up 12v to 230v AC on the
inverter so then back down 240AC down to 12vdc for sat boxes all drawing precious power away to transform the power.
I hope that isn't gobbledygook
