Who are the bright 'SPARKS' ( LECKKIES ) out there?

[Andy the Coastie]

I'm thinking NOW about getting one of these http://www.machinemart.co.uk/rangeguide.asp?t=564 and running it off the spare cranksharf pulley on one of my engines .

Now, can anyone please explain to me what would 6 Kva run on 240 volts ?

Mainly want it for the microwave, laptop, kettle and charging of dive torches whilst transiting to dive sites ... etc etc .

Many thanks in advance

[Mick F]

Originally Posted by Andy the Commie

I'm thinking NOW about getting one of these http://www.machinemart.co.uk/rangeguide.asp?t=564 and running it off the spare cranksharf pulley on one of my engines .

Now, can anyone please explain to me what would 6 Kva run on 240 volts ?

Mainly want it for the microwave, laptop, kettle and charging of dive torches whilst transiting to dive sites ... etc etc .

Many thanks in advance

Andy,

It should safely run 2 x 13A 3 pin domestic plugs (yer normal everyday plug) at full draw. So you have (about) 26 Amps to play with....

Your Kettle & m/Wave would draw the most power. Normal Kettle would draw in the region of 10 - 12 Amps. Microwave (750W) draws about 3.25A. Being cautious, this leaves about 11 Amps.

Dive torches draw sod all, as most are through converters to DC & regulated down to 6/7.2/9/12/17V trickle chargers, so they can be ignored. Laptops take a bit more, but usually a max of 16V at about 3.5A.

So lets see:

Kettle 3000 KVA
Microwave 750 KVA
3 x Torches 50 KVA
2 x Laptop 220 KVA

Total 4020 KVA

Safely within the limit of the genny.

HTH

[wreckweasel]

6000/240 is approx 24amps.

[Rob Evans]

Yup, what Mick said. If you equate Watts=VA (Kilowatts=KVA), you can figure it from there..

[Andy the Coastie]

Cheers guys,,,,

The main man in the shop told me that one off his Past sales assistants, had one of these alternators on his VW Camper, so he had 240 vlot when at the beach surfing ,,, ran his 800 w microwave, kettle and electric drill at the same time.....

so, think this is the route to go , and get one fitted... smaller than a GENNY... no noise , and using an engine thats already running

Now , just need to find a ELECTROMAGNETIC CLUTCH to power the compressor.

[NeilB]

Rather than have the complexity of electromagnetic clutchs and mounting the genny with pullies, belts etc have you considered an iverter or two? You can get them quite cheaply upto 2500w and they just connect to your batteries. You then have 240v AC all the time.

[David Wallace]

Originally Posted by NeilB

Rather than have the complexity of electromagnetic clutchs and mounting the genny with pullies, belts etc have you considered an iverter or two? You can get them quite cheaply upto 2500w and they just connect to your batteries. You then have 240v AC all the time.

A 12v inverter running 2500w would be drawing a max of 180 amps from the battery bank put 3 in and at full power thats a lot of draw from the batteries.

So as well as the £400 per inverter, that battery bank would have to be beefed up - count on about £90 per 120 amp/hour marine battery you add.

Then you have to upgrade the alternater to get the charge back into the batteries as you use it.

seems like a huge cost to me.....

[nigelH]

Originally Posted by Andy the Commie

I'm thinking NOW about getting one of these http://www.machinemart.co.uk/rangeguide.asp?t=564 and running it off the spare cranksharf pulley on one of my engines.

Not knowing much about boat engines can you supply a constant(ish) RPM with just a belt? The volts/frequency is going to depend on the 3Krpm and going overspeed will go overvolts and rapidly get unhealthy for the insulation (overvolting a microwave is terminal).

[Woz]

Electromagnetic and manual industrial clutches:

www.lenze.co.uk

[Andy the Coastie]

I don't really want to put on and inverter, as the one i have at the minute ( 300 w ) is powering my NAV LAPTOP.

The idea is to get a alternator from machine mart, put on a bracket and run from main diesel engine while boat is going alone, the engine doesn't rev more than 2,200.

On a fast ilde @ 800 RPM , they say this is just as good at supplying 240 volt as it would at 2,220.......... over 3000 rpm, and ya start going though brushes