Cable size for Electric toilet

[rigpigpaul]

Hi All, I want to buy a 12 volt Jabsco lite electric toilet. I have read that I need a 25amp fuse. What size cable will I have to use. The toilet will be 6 meters from the electric panel. Thanks in anticipation
RPP

 

[nimbusgb]

At 25 amps for a 1% voltage drop 50mm squared! For a 3% drop 25mm squared

Suspect the running load is more like 10 to 15 amps so 10mm sq will give 3% at 6m and 15 amps.

The short answer is 'the biggest you can afford'.

You may need to resize the feeds to your electric panel too. May be simpler to run direct from battery location with dedicated fuses.

 

[Glyka]

At 25 amps for a 1% voltage drop 50mm squared! For a 3% drop 25mm squared

Suspect the running load is more like 10 to 15 amps so 10mm sq will give 3% at 6m and 15 amps.

The short answer is 'the biggest you can afford'.

You may need to resize the feeds to your electric panel too. May be simpler to run direct from battery location with dedicated fuses.

When computing voltage drop we use the full length of the wire i.e. positive and negative lengths. In this case 6+6=12 meters.

I have uploaded a very useful excel file that you can download from here http://automaton.gr/Files/CableSelection.xls (it's on my server so most probably safe).

 

[David2452]

I have installed four electric heads in the last couple of months, all on live aboards (still have a couple waiting on the books), they are becoming very popular. Each one has had a dedicated supply from the switched side of the domestic bank via a midi fuse, taking from a panel is usually not suitable due to exess voltage drop unless it is supplied by very heavy cable, the macerator needs plenty of power to be efficient so work out the cable run carefully to give no more than 8% drop, use quality tinned cable and well made good quality crimps for a lasting job. On the last one I used 16mm2 cable terminating in a small fuse block and a power post for the return then connected the heads own cable and suitable fuse via that, also connected the shower gulper pump to the block and it ran far better than on the original supply. Here's a good cable calculator for you. You will need to use 20a @ 12v for your cable calculation on that model, don't forget the cable run is supply positive and negative cables combined and protect the main feed with a fuse appropriate to it's weight.
http://www.calculator.net/voltage-drop-calculator.html?material=copper&wiresize=1.634&voltage=12&phase=dc&noofconductor=1&distance=40&distanceunit=feet&amperes=22&x=71&y=12

 

[rigpigpaul]

Thanks all for the advice, just what i was looking for. The boat is in Turkey and I will buy the toilet through West Marine but I want to buy the cable and bits online and take them out with me. Names of any reliable suppliers would be grateful. Thanks aga

 

[VicS]

Thanks all for the advice, just what i was looking for. The boat is in Turkey and I will buy the toilet through West Marine but I want to buy the cable and bits online and take them out with me. Names of any reliable suppliers would be grateful. Thanks aga

One place often recommended for good service and competitive prices is Furneaux Riddall. http://www.furneauxriddall.com/

 

[mocruising]

We fitted on a few years back but on a 24 V system. The installation manual stipulated the cable size.

 

[vyv_cox]

We have had a Jabsco LiTE for a few years now, and like it a lot. On our installation the joker valve is at the lowest point and probably will be on many others. Perhaps due to the small amount of water it uses to flush we find that the joker valve housing tends to salt up a lot, which deforms the rubber of the valve, upon which it leaks back into the bowl. Suggest you buy a couple of spares to take with you.

A weak link that I suspect is the belt that drives the impeller. If this fails there is no easy way to fix it. Jabsco sell a spare one for about £25, horrendous price but a worthwhile investment IMHO.