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roverrescue
29th January 2009, 02:01 PM
Not directly LR related but my 130 is the tow vehicle when needed :)

FACTS
-9m plate Al cabin boat.
-200hp Vovlo Penta DuoProp stern drive.
-12V charging system that charges starter batts and one house battery.
-Plenty of room to attach another belt driven ancillary.


PROBLEM
We now have a 100L brine freezer that uses a 240V 3.2A compressor (770W ++ startup draw).
To operate on the boat we can use a 2.4kVA generator when necessary.
The freezer unit pulls down to -35 in an hour, with sal****er slush it will hold cold for a long long time. So thinking we could somehow use the Volvo to power the compressor on the run out to the reef (1-2 hours) plus any moving around etc etc and the run home.


Option 1
240 V belt driven generator

-nice and easy in theory but:
3600rpm consistent shaft speed to ensure voltage and frequency, not impossible as the Volvo is pretty much always run at same RPM when cruising.
How hard would it be to wire up some form of regulator/ clutch that will only engage the gennie when "x" RPM is reached.



Option 2
120A alternator 12V wired to the house battery and then say a 2 or maybe would need 3 kVA inverter.

-seems doable, alternator would be easy enough but will say a 2kVA inverter startup a 240V 3.2A compressor motor?



Any thoughts appreciated.
Steve

BigJon
29th January 2009, 02:29 PM
I think the invertor would be the easiest system to set up. You then get the bonus of a stable 240v output for running other things as well.

roverrescue
29th January 2009, 02:37 PM
Good point.
I think the stable 240V is probably an important point.
Will need to try a 2kVA inverter on the compressor me thinks.

S