Also worth installing a switch to the terminals so you can turn the B2B charger on/off easily.
In our case we have a circuit breaker normally off, only connecting the DC>DC charger when needed. The Victron Orion DC>DC smart can be switched into a power supply mode if necessary to power domestics like lights, VHF etc. So we have some options.
Victron B2Bs don't have fans, just a large finned heatsink to the rear. Also limited to 30amps at 12v.
Yes, I've used them but a bit small for some applications and of course as noted above they get really hot because of it - I have two 60 amp Renogy on my own boat as I have two 125A alternators so a 50% duty cycle seems as high as I should go to keep long life in the alternators. (As a side note why the heck my two 20 hp Yanmars ONLY come with 125a alternators from the factory is another question )
20hp?
Being a 24v boat, we use the Victron 17amp B2B so 34amp in 12v money. Its not a primary source of charging so I don't really expect to need it. We can charge from the generator at 100 amps at 24v if we needed to. I really don't expect to do that either.
Yes, the original spec for the Quasar 50 was a pair of 20 hp engines. Mine had been converted as some time to a pair of 3GM30 and many have 45s etc as for some reason people these days always think bigger is better. I changed back to new 3YM20s which saved £40 kg at the back of the boat, use 1L an hour at 2000 rpm where we make 7 kn in calm water and at full revs we can do 10 knots which is more than enough and there is enough power to push through rough seas if needed. The boat only weights about 8 tonnes since I rebuilt her so its more than enough.
Hmm, How do you get a 13t boat down to 8t?
The original weight from the factory is 9.5 tonnes (the wider 23 foot version of the Quasar was heavier) but we removed 3 large skips full of material, replaced everything except the main bulkhead with lightweight materials, removed 2 of 4 heads and all associated bulkheads (non structural) some corridor ceilings, some 80 kg of wire by using a distributed network, and on and on, All doors are blown pvc board so weigh nothing, sole boards are 10mm foam core ply composite, no flex but very light, lighter engines, changed the fuel tanks from the original 500L of stainless to 200L of HDPE, removed the pushpit and pulpit , removed the 60kg front platform between the nets and welded an 11kg alloy one instead, saved 50 kg on the battery bank (and trebled the size in lIfepo4) rebuilt the entire galley in lightweight materials etc.
Sounds like you have done a massive amount of work. Still amazed you can get anywhere near 8t.The original weight from the factory is 9.5 tonnes (the wider 23 foot version of the Quasar was heavier) but we removed 3 large skips full of material, replaced everything except the main bulkhead with lightweight materials, removed 2 of 4 heads and all associated bulkheads (non structural) some corridor ceilings, some 80 kg of wire by using a distributed network, and on and on, All doors are blown pvc board so weigh nothing, sole boards are 10mm foam core ply composite, no flex but very light, lighter engines, changed the fuel tanks from the original 500L of stainless to 200L of HDPE, removed the pushpit and pulpit , removed the 60kg front platform between the nets and welded an 11kg alloy one instead, saved 50 kg on the battery bank (and trebled the size in lIfepo4) rebuilt the entire galley in lightweight materials etc.
Now to clarify the weight - two readings - one at 8 tonnes when dropped in after the rebuild but with dry water and fuel tanks and no possessions on board - lightship weight as its called (though unlike the manufacturers it did at least have oil and coolant in the engines) - more recently when it came out for the lighter engines but we were living aboard and had water in the tanks (900L full, so a full fuel and water load is over 1.1 tonnes, though I foolishly forget to check how much water was in when it was lifted) and possessions aboard it was 9.3 tonnes (on a different lift). I fitted two water makers so that I could, if required keep the tanks with just 100L a side to keep weight nearer the 8T mark than the 9T mark but setting out for the circumnavigation all bets are off as we have about 300Kg of cat food alone aboard and another 100kg in cat litter stores as well as spares and two very heavy spare sails. We are now sitting within 1cm of the original water line (still not quite down to that mark) whereas in normal local trim we are 2-3 inches off the marks.
I have not yet reached the obsessiveness of the guy I shared a pontoon with for two years with a high mast Rapier 400 rocket ship who even changed and weighed all his water pipe because it was built with the alloy cored plastic that was in vogue then and he saved 12kg by changing it all to Hep20 .
One of my cats is very fussy! Cosma pure skipjack tuna and shredded chicken breast (£12/kilo and human food grade - not bad for a street cat from Spain!!)Sounds like you have done a massive amount of work. Still amazed you can get anywhere near 8t.
A lagoon 52, as declared is 26t.
We know from experience of two catamarans that weight, or lack of it, is everything in a catamaran.
By the way, you can buy cat food in every supermarket in the Caribbean
She does but you are quite right that with cats there is a constant compromise between sufficient spares and supplies for long term self reliance and weight to still perform. We will not be carrying spare engine pistons aboard!Wow, you have been busy.
I am sure she will say well if kept very light