Battery cable - few question

[slawosz]

Hi,
I am planning to move one battery to the other side of the boat. Battery is big, 110 Ah, boat is small (Sadler 25). 2 batteries barely fit under the quarter berth, so I decided to move it to the other side. Now, I will need long cable to connect to battery. I am planning to buy 50mm2 cable, just to be safe - apparently 1gm10 is drawing 200 Amps when starting.
I have 2 question:
- will be 1.5 meter cable not too long and won't cause too much voltage drop?
- can I connect negative on both batteries to negative point on starter motor? (now batteries are linked and there is one cable to starter motor
- can I use automotive cables widely available on ebay?

Thanks!

 

[Boater Sam]

That's 3 questions, Yes yes & yes providing its stranded preferably tinned cable not the stuff with only 7 or 19 copper wires in.

 

[PaulRainbow]

Hi,
I am planning to move one battery to the other side of the boat. Battery is big, 110 Ah, boat is small (Sadler 25). 2 batteries barely fit under the quarter berth, so I decided to move it to the other side. Now, I will need long cable to connect to battery. I am planning to buy 50mm2 cable, just to be safe - apparently 1gm10 is drawing 200 Amps when starting.
I have 2 question:
- will be 1.5 meter cable not too long and won't cause too much voltage drop?
- can I connect negative on both batteries to negative point on starter motor? (now batteries are linked and there is one cable to starter motor
- can I use automotive cables widely available on ebay?

Thanks!

35mm cable will be fine.

Both negatives are OK.

Automotive cable or welding cable will be OK

 

[slawosz]

Thank you very much. I promise to learn to count to 3 and read the corresponding chapters of the smart book I bought!

 

[Bristolfashion]

On undertaking a similar job, the supplier suggested conventional cable rather than specific marine cable for a completely internal job - using the good quality stuff, the price difference was considerable. Been in service 3 years with no problems.

 

[vyv_cox]

On undertaking a similar job, the supplier suggested conventional cable rather than specific marine cable for a completely internal job - using the good quality stuff, the price difference was considerable. Been in service 3 years with no problems.

I wired my windlass using untinned welding cable more than 20 years ago. Still perfectly ok.

 

[Alex_Blackwood]

Hi,
I am planning to move one battery to the other side of the boat. Battery is big, 110 Ah, boat is small (Sadler 25). 2 batteries barely fit under the quarter berth, so I decided to move it to the other side. Now, I will need long cable to connect to battery. I am planning to buy 50mm2 cable, just to be safe - apparently 1gm10 is drawing 200 Amps when starting.
I have 2 question:
- will be 1.5 meter cable not too long and won't cause too much voltage drop?
- can I connect negative on both batteries to negative point on starter motor? (now batteries are linked and there is one cable to starter motor
- can I use automotive cables widely available on ebay?

Thanks!

Is it possible for you to fit a + Busbar equidistant between the two batteries ? Take all your feeds etc from that. You would then have equal volt drop and cable resistance from each battery.

 

[fisherman]

We had welding cable installed to a distant start battery from new, never gave a problem.

 

[Mudisox]

I have some spare 35mm used to feed front winch and heater.. pm me if you wish.

 

[vyv_cox]

Hi,
I am planning to move one battery to the other side of the boat. Battery is big, 110 Ah, boat is small (Sadler 25). 2 batteries barely fit under the quarter berth, so I decided to move it to the other side. Now, I will need long cable to connect to battery. I am planning to buy 50mm2 cable, just to be safe - apparently 1gm10 is drawing 200 Amps when starting.
I have 2 question:
- will be 1.5 meter cable not too long and won't cause too much voltage drop?
- can I connect negative on both batteries to negative point on starter motor? (now batteries are linked and there is one cable to starter motor
- can I use automotive cables widely available on ebay?

Thanks!

You might like to look at the Smartgauge website advice on connecting batteries SmartGauge Electronics - SmartGauge and SmartBank wiring diagrams

My domestic bank of three is connected this way. Not exactly answering your question but useful info.

 

[VicS]

You might like to look at the Smartgauge website advice on connecting batteries SmartGauge Electronics - SmartGauge and SmartBank wiring diagrams

My domestic bank of three is connected this way. Not exactly answering your question but useful info.

The SmartGauge site seems to have been revised since I last looked at it
The old page on wiring multiple battery banks can still be found though

Dunno if this is what you were really hoping to link to ......... SmartGauge Electronics - Interconnecting multiple batteries to form one larger bank

.

 

[slawosz]

Thanks for your answers. I already have a 1-2-Both-Off switch which is doing a good job, and I am willing to keep it. The current installation seems to work, I just need to replace short cables with longer ones.
One more thing - I need to lead the cable across the engine bay, in front of the engine. Obviously, I will use PCV pipe for this, but is there anything I need to look out I might not know of?

 

[vyv_cox]

The SmartGauge site seems to have been revised since I last looked at it
The old page on wiring multiple battery banks can still be found though

Dunno if this is what you were really hoping to link to ......... SmartGauge Electronics - Interconnecting multiple batteries to form one larger bank

.

The page I linked to includes the battery bank wiring but I did not find the old page about that so thanks.

 

[andsarkit]

My 1GM10 draws 80A and starts almost instantly. When I had the batteries removed for the winter I started it with a 24Ah battery and 3m long 10mm2 cables without any problem. Unless yours is particularly difficult to start , you would probably be fine with 35mm cables.
I don't have a large crimp tool so I solder the lugs and cover the join with adhesive heatshrink which makes them waterproof. I've had no problem using untinned cable. The most likely cause of problems is corroded or loose connections.