Wiring up my searider

[henryfreston]

Hi guys I have a few questions in regard to wiring up my boat.

Basically I have a forward 'd class style' console with a center console sitting behind it. The battery has a compartment in the front console.

I need to know the name of the item that can be used to connect several wires into one. What I mean is, if you have all your different wires for different things e.g. vhf, gps etc. Then can you connect all these wires into a component which then only has one pair of wires leading out I can connect to my battery (and also so I can install a main switch into this main wire.

Hope that's explained ok!

Cheers

[JamesF]

Possibly "bus bar"?

[Harrys Game]

Any DIY store or electrical outlet will sell "chocolate block" sometimes called "choc block" these come in 5A 10A 15 Amp and so on, my suggestion is get the size that will accommodate the amount of wires you want to bunch together . Personally 15 amp works for me. If its going to be exposed to seawater or the elements a encasement might be a good idea. Electrical plastic enclosures are available in the same places. Finally before putting the front cover on a squirt of WD 40 is beneficial. Inline fuses in both pos and neg should safeguard you . If you want a switch or isolator thats not going to cause any problems.Depends on what sort of standard you want to work to glands are available to seal the entry of the cables or there is good ole silicon. Regards Jim

[treerat]

Or you connect each wire up to a switch unit which has one pair of wires coming out to the main isolator.

boat switch panel | eBay

[henryfreston]

Thanks for the responses!

For how I understand it:

You have all the positive wires from the appliances running into one fuse box, which then has one wire which leads to the battery. Then on the negative side you have all the wires from the appliances running to a bus bar, and again one wire from the bus bar running to the battery.

Am I right?

Also would you connect a big switch which can break the main positive wire heading back to the battery?

Henry

[ShinyShoe]

Yes to all of the above.
Need to think if you have any kit that should be permanently on
Need to think where the charge wire goes to from the engine (I'd put it battery side of the isolator switch but I could be wrong)

[henryfreston]

Originally Posted by ShinyShoe

Yes to all of the above.
Need to think if you have any kit that should be permanently on
Need to think where the charge wire goes to from the engine (I'd put it battery side of the isolator switch but I could be wrong)

I will install a switch panel so i can turn on stuff individually (anything that needs to be on permanently can be left on using swtich).

The outboard will have its own terminals which can just connect straight onto the battery can't they? Or does that connection have to be broken by a switch also?

[Harrys Game]

Henry, you are working with DC there is no neutral and positive it is positve 12v and neg 12v so bearing in mind I was used to working on steel ships so fusing the pos and neg was standard. So to simplify take a pos wire from the battery and a neg wire. These need to be bigger than the sum total of the wires you are going to add for your devices. Take these into a switch that will break both poles ie pos and neg( I think thats a wiser way) then you need to ideally go into a fuse block (available on evil bay) then from the other side feed your device you loop across the base to the next fuse to feed the next device and so on all negs can go into a connector block.
That should do you. Regards Jim. If my explanation is not clear enough pm me and I will sketch up something and email it.

[ShinyShoe]

I *think* putting a switch in the engine feed is bad. Certainly some car engines don't like it if the battery is suddenly switched off - it dumps a load of power back into the engine electrics and you could need to buy a new ECU! Bad design in my opinion!

So I'd say connect engine direct to battery.

Bet ya someone is along in 5 to say "NO thats a fire hazard" or somet

[Harrys Game]

Totally agree with above , alternators do not like going from load to open circuit they tend to blow diodes! Regards Jim

[Festinghouse]

Originally Posted by ShinyShoe

I *think* putting a switch in the engine feed is bad. Certainly some car engines don't like it if the battery is suddenly switched off - it dumps a load of power back into the engine electrics and you could need to buy a new ECU! Bad design in my opinion!

So I'd say connect engine direct to battery.

Bet ya someone is along in 5 to say "NO thats a fire hazard" or somet

in motorsport its common practice to have the kill switch on the negative, as ignition systems can continue running on the alternator if the positive side is cut which then damages the ignition system.

[TRevor Lawson]

you are correct it is damaging to shut off power to engine suddenly on our race cars the master batt switch has a resister wired in to absorb the spike to earth

[CUSAC]

I found that looking at example wiring diagrams from others really helped when replacing the wiring on our RIB. I have attached the one I drew up which I hope is helpful. Fairly basic set up incorporating isolator switch, carling switch panel, fuse box and bus bar. The engine is wired through the isolator switch primarily to ensure everything is actually off when the boat is left and the switch is a high quality blue sea systems one so not too worried about power being cut.

[Nos4r2]

CUSAC's wiring diagramme is a good one. Use it and add/remove components as necessary.
I'd use a Blue Sea 5025 fuse box (it includes a negative busbar so makes it a shedload easier).

Please please PLEASE avoid using chock blocks. They have no place on a boat,particularly not something as bouncy as an SR4 and nobody who'd use them will ever get near my wiring. They fail. It's what they do.

[Chris]

Henry...

Some answers for you.

1 work out how many devices you have to power and get a fuse panel that meets the requirement with a couple of extra slots for future additions.

2 Run all the devices off individual fuses. Remember as well as the device failing the fuses are there to protect against the cabling between the fuse box and the device chaffing and shorting (much more likely to happen than the device shorting IMO).

3 The engine negative runs straight to the battey. The engine positive should run through an isolator switch so you can turn off power to the engine. What if the battery cables short out in the engine ? You need to be able to isolate the engine. Just don't switch it off if the engine is running (Simples !)

4 All your device negatives connect into a busbar then to the battery.

5 There is one exception to the above. The VHF should connect directly to the battery and have its own in line fuse. Reason being is if your wiring fails you can still call for help...!

6 I am 20 mins away and in the middle of wiring up Taurus. Got a pair of battery cables for you if you need some (no charge) and a few other other odds and sods...

[henryfreston]

Hi guys

Just finished to processing all that

I understand most of the diagram now. So would be relatively confident in wiring it up now. But what I am not sure of is what the block are that intercept all the appliances leading to the fuse box from the A-Frame (those 5 blocks). I Know it's something to do with the readers coming from the outboard e.g. trim gauge. But I don't quite understand it!

[henryfreston]

Originally Posted by Chris

Henry...

Some answers for you.

1 work out how many devices you have to power and get a fuse panel that meets the requirement with a couple of extra slots for future additions.

2 Run all the devices off individual fuses. Remember as well as the device failing the fuses are there to protect against the cabling between the fuse box and the device chaffing and shorting (much more likely to happen than the device shorting IMO).

3 The engine negative runs straight to the battey. The engine positive should run through an isolator switch so you can turn off power to the engine. What if the battery cables short out in the engine ? You need to be able to isolate the engine. Just don't switch it off if the engine is running (Simples !)

4 All your device negatives connect into a busbar then to the battery.

5 There is one exception to the above. The VHF should connect directly to the battery and have its own in line fuse. Reason being is if your wiring fails you can still call for help...!

6 I am 20 mins away and in the middle of wiring up Taurus. Got a pair of battery cables for you if you need some (no charge) and a few other other odds and sods...

Hi Chris, thanks that's really nice and clear and made me understand it better

If it doesn't waste your time too much then by all means pop down that would be really useful!

Henry

[CUSAC]

Originally Posted by henryfreston

Hi guys

Just finished to processing all that

I understand most of the diagram now. So would be relatively confident in wiring it up now. But what I am not sure of is what the block are that intercept all the appliances leading to the fuse box from the A-Frame (those 5 blocks). I Know it's something to do with the readers coming from the outboard e.g. trim gauge. But I don't quite understand it!

The 5 blocks between the fuse box and the a frame parts are the switches. It is slightly more complicated as the switches light up when on and can be backlit off the ignition (thats why they link to the rev counter). If you just have a simple switch panel then you can ignore much of whats happening with those switches and it is much simpler.

[henryfreston]

Originally Posted by CUSAC

The 5 blocks between the fuse box and the a frame parts are the switches. It is slightly more complicated as the switches light up when on and can be backlit off the ignition (thats why they link to the rev counter). If you just have a simple switch panel then you can ignore much of whats happening with those switches and it is much simpler.

Ok thanks, I am going to order;

1x busbar
1x switch panel
1x master switch


comes to around £50 which isn't too bad- from mailspeedmarine.

[jumpinjack]

Is that a waterproof switch panel Henry?
The non sealed ones are generally a bit cheaper.