Inverter

[Refueler]

Inverters ... simple answer as long as you buy a decent wave form version ... BUT the losses involved make this a very inefficient solution ...

12v to 240v ... losses
240v to charger ... losses

I value each Ah I have in my on board batterys ....

 

[PaulRainbow]

No lithium batteries involved, Paul. Just wire the 12 V tool minus it's battery straight to the boat's system.

Apologies Alan, i misread what you said.

 

[William_H]

Re Refueler replacing batteries in drill. My most successful replacement was in a very old Ryobi 7.2v drill originally using NiCad batteries in the handle. I fitted 2x 18650 cells in series hard wired to switch and motor. I fitted a 2cell charge controller for charging with a series resistor to limit charge current when charged from 12v 1pcs 2S 3A 7.4V 8.4V Li-Ion BMS PCM Battery Protection Board PCM for 18650 Lithi | eBay
Note the c ontroller supposedly would control discharge cutting off at low battery voltage but had no chance of carrying drill start up current. So I just have to be careful not to flatten batteries. ol'will

 

[SteveIOW]

Thank you for varied advice above which has given me food for thought but still not decided on which way to go.

1. Connecting tool direct to boat battery: I have tried this. I have an old 12v Makita drill on board. All 3 of the NiCad batteries it came with are duff. I soldered wires direct to the contacts within the drill handle with crocodile clips at the other end to connect to boat battery. However, even with the boat battery charged to more that 13v, the drill ran very slowly. Maybe the wires needed to heavier cross section, Tried to keep wire length to minimum but this did limit where I could use the drill. (The drill was nice and light though with no battery pack fitted.

2. Charging tool battery pack direct from 12v boat battery: I didn't know this was an option but some posts above say that it is. Does anyone have details of what make/model of rechargeable tools has a charger that accepts a 12vDC input to the charger?

3 Inverter: This seems a viable option but odd that this means going from alternator to 12vDC boat battery to 12DC/240AC Inverter to Tool Charger with DC output to Tool Battery. However this does give the option of using 240vAC for other things.

 

[Alan S]

A 12 Volt drill connected directly to boat's battery with reasonably short and heavy wires should definitely be as powerful as with its own battery. I have about 3 metres of 1.5mm2 flex and it works just fine. Sorry Can't help re charger.

 

[wingcommander]

Thank you for varied advice above which has given me food for thought but still not decided on which way to go.

1. Connecting tool direct to boat battery: I have tried this. I have an old 12v Makita drill on board. All 3 of the NiCad batteries it came with are duff. I soldered wires direct to the contacts within the drill handle with crocodile clips at the other end to connect to boat battery. However, even with the boat battery charged to more that 13v, the drill ran very slowly. Maybe the wires needed to heavier cross section, Tried to keep wire length to minimum but this did limit where I could use the drill. (The drill was nice and light though with no battery pack fitted.

2. Charging tool battery pack direct from 12v boat battery: I didn't know this was an option but some posts above say that it is. Does anyone have details of what make/model of rechargeable tools has a charger that accepts a 12vDC input to the charger?

3 Inverter: This seems a viable option but odd that this means going from alternator to 12vDC boat battery to 12DC/240AC Inverter to Tool Charger with DC output to Tool Battery. However this does give the option of using 240vAC for other things.

Definitely Dewalt 18volt batteries. The off grid ciggie lighter charger doesn't come cheap though . Mine was an offer at time of purchase still £40 dabs on top of the drill and standard 240 volt charger

 

[SteveIOW]

Now that I know DeWalt, and Makita, do a charger taking their standard batteries, with 12v DC input and 10.8v - 18v output, I have decided that is the way to go. I already have an 18v Dewalt drill with two rechargeable batteries, so all I need to get is the DC119-XJ charger.
Thank you all for suggestions,
SteveIOW

 

[wingcommander]

Now that I know DeWalt, and Makita, do a charger taking their standard batteries, with 12v DC input and 10.8v - 18v output, I have decided that is the way to go. I already have an 18v Dewalt drill with two rechargeable batteries, so all I need to get is the DC119-XJ charger.
Thank you all for suggestions,
SteveIOW

Just be aware of the fuse situation. Their is a 10 amp fuse built-in to the ciggie plug . However the first time I plugged in the van socket it blew spade 10 amp in the van fuse board. Engine was not running so only 12.7 volt battery. I replaced this and now only plug in with Engine running . So the higher voltage from alternator means less amps required. I guess the fuse in the plug must be a slow blow type .
Obviously you can increase the fuse rating if your inline fuses are too sensitive.

 

[jac]

Obviously you can increase the fuse rating if your inline fuses are too sensitive.

As long as the fuse is still of a suitable size to protect the wiring

if not - fairly cheap to get a few metres of larger gauge wiring - certainly much cheaper than rewiring the whole boat when the all wiring goes up !!!

 

[William_H]

Just be aware of the fuse situation. Their is a 10 amp fuse built-in to the ciggie plug . However the first time I plugged in the van socket it blew spade 10 amp in the van fuse board. Engine was not running so only 12.7 volt battery. I replaced this and now only plug in with Engine running . So the higher voltage from alternator means less amps required. I guess the fuse in the plug must be a slow blow type .
Obviously you can increase the fuse rating if your inline fuses are too sensitive.

Interesting The current reduction should be in the ratio 14v (with alterntor charging) to 12.7 volts or perhaps a bit less (battery not on charge) So 10 amp drain of inverter with alternator charging should increase to 11 amps on battery alone. Increasing more as battery discharges. (if my maths are correct.) Perhaps you can find a 12amp fuse for Van board. Assuming the wiring is OK for more current protection level. ol'will

 

[wingcommander]

As long as the fuse is still of a suitable size to protect the wiring

if not - fairly cheap to get a few metres of larger gauge wiring - certainly much cheaper than rewiring the whole boat when the all wiring goes up !!!

Isn't that the reason bacofoil was invented? Instant emergency fuse .

 

[SteveGorst]

You've had some good replies here but re the vacuum cleaner. We use a cheap 240 volt 1kw vacuum cleaner off the 2kw inverter and my wife loves it. Ok its grossly inefficient but the solar panels do put the power back in pretty quickly. I guess the trick is to only do your vacuuming on a sunny day.

 

[Laysula]

Can't help with the hoover, but for power tools just sit in your nearest pub by a plug socket and have a couple of pints whilst charging.

 

[Kelpie]

You've had some good replies here but re the vacuum cleaner. We use a cheap 240 volt 1kw vacuum cleaner off the 2kw inverter and my wife loves it. Ok its grossly inefficient but the solar panels do put the power back in pretty quickly. I guess the trick is to only do your vacuuming on a sunny day.

We chose the same approach. You only actually run a hoover for a few minutes so it barely makes any dent in the battery.
Ours is a £30 unbranded wet and dry type. Cannot fault it.