New Battery Bank set up

[Robbo]

1 hour ago, rusty69 said:

Sounds like a good idea. 

Do they go bigger than 300A?

Do the ignition protected ones allow them to be safely  mounted in the battery box (which I guess is the idea). 

I think 300a is the max, and yes ignition protected.

[jddevel]

5 hours ago, WotEver said:

So if you have an inverter wired through it that can pull 300A you'd want at least a 400A busbar

The only 400 amp busbar I can currently find is a chamber type and extremely expensive. Advice where to look please.

[WotEver]

5 minutes ago, jddevel said:

The only 400 amp busbar I can currently find is a chamber type and extremely expensive. Advice where to look please.

Blue Sea do a neat 600A one: https://www.bluesea.com/products/2104/PowerBar_600A_BusBar_-_Four_3_8in-16_Studs

[rusty69]

10 minutes ago, jddevel said:

The only 400 amp busbar I can currently find is a chamber type and extremely expensive. Advice where to look please.

http://www.furneauxriddall.com/cgi-bin/ss000004.pl?page=search&SS=Busbar+&PR=-1&TB=O&ACTION.x=0&ACTION.y=0

http://www.aquafax.co.uk/catalogue/1834-600a

 

As per last time you asked

 

Edited July 17, 2017 by rusty69

[WotEver]

Here it is on Ebay:

http://m.ebay.co.uk/itm/292091611237?_mwBanner=1

The Blue Sea one that is 

[jddevel]

29 minutes ago, rusty69 said:

As per last time you asked

Not for the first time I`ve forgotten what I`ve asked!!!! The Furneaux Riddell certainly seem competitive. Thank you

[jddevel]

Is it better to limit the number of connections to each stud on a busbar or is it determined purely by the height of the stud please?

[WotEver]

1 minute ago, jddevel said:

Is it better to limit the number of connections to each stud on a busbar or is it determined purely by the height of the stud please?

It really doesn't matter as long as the connections are secure, clean, and not under any strain. Obviously one connection per stud is neater and more convenient for maintenance but there's no 'rule'. 

[jddevel]

Thank you. WotEver

[Robbo]

9 hours ago, WotEver said:

It really doesn't matter as long as the connections are secure, clean, and not under any strain. Obviously one connection per stud is neater and more convenient for maintenance but there's no 'rule'. 

I would disagree.  The connection at the top of the stud is not as good as the connection at the bottom.  For low current devices this isn’t really an issue but for high current devices it’s best to keep them to 1-2 connections to a stud with the largest been next to the busbar.

[WotEver]

Just now, Robbo said:

I would disagree.  The connection at the top of the stud is not as good as the connection at the bottom.  For low current devices this isn’t really an issue but for high current devices it’s best to keep them to 1-2 connections to a stud with the largest been next to the busbar.

I challenge you to demonstrate the difference in a real world situation. It would not present a problem. 

[rusty69]

Just now, WotEver said:

I challenge you to demonstrate the difference in a real world situation. It would not present a problem. 

Jeez, I didn't realise anyone here was from the real world. 

[WotEver]

Just now, rusty69 said:

Jeez, I didn't realise anyone here was from the real world. 

It's a temporary aberration. I shall return to my nurse shortly. 

I agree that the highest current devices should be at the bottom of the stud btw but even that doesn't really matter an awful lot. 

[Robbo]

2 minutes ago, WotEver said:

I challenge you to demonstrate the difference in a real world situation. It would not present a problem. 

Starter motor connection, one big one and loads of small connections.  You don’t get good connection on both sides to the largest cable and you have a bunch of cables coming out of it from all angles.

[WotEver]

1 minute ago, Robbo said:

You don’t get good connection on both sides to the largest cable and you have a bunch of cables coming out of it from all angles.

Read again what I wrote initially:

"as long as the connections are secure, clean, and not under any strain"

[Robbo]

Just now, WotEver said:

It's a temporary aberration. I shall return to my nurse shortly. 

I agree that the highest current devices should be at the bottom of the stud btw but even that doesn't really matter an awful lot. 

If you but a small connnection at the bottom and the largest at the top you’ll then reduce the amount of contact between the stud and cable.

Just now, WotEver said:

Read again what I wrote initially:

"as long as the connections are secure, clean, and not under any strain"

And that means not connecting more than a couple to a stud, and especially not of widely different sizes.

[WotEver]

2 minutes ago, Robbo said:

If you but a small connnection at the bottom and the largest at the top you’ll then reduce the amount of contact between the stud and cable.

No, because they will all terminate with 8mm (or whatever) lugs. So all contact faces will be of similar size regardless of the cable size. 

[Robbo]

Just now, WotEver said:

No, because they will all terminate with 8mm (or whatever) lugs. So all contact faces will be of similar size regardless of the cable size. 

yiu don’t want to rely on the bolt for the connection, it’s the bus bar they are connecting to.  Adding more lugs in between just adds more connections.   It’s also hard to actually wire any more than 2 to a bus bar due to routing anyhow!

[WotEver]

A connection to a stud will be... metal of the busbar, metal of the lug, metal of the next lug (etc), washer. Then the nut on top will squash all of those faces together. So as long as "the connections are secure, clean, and not under any strain" it will be fine. 

[Tony Brooks]

After al this I am still wondering why the Mikuni seems to be fed from the batteries rather than the master switch. I though all bar a few special exemptions, of which a heater is not one, had to be via the  switch. That looses one connection at the batteries.

What have I missed?

[WotEver]

5 minutes ago, Tony Brooks said:

After al this I am still wondering why the Mikuni seems to be fed from the batteries rather than the master switch. I though all bar a few special exemptions, of which a heater is not one, had to be via the  switch. That looses one connection at the batteries.

What have I missed?

One of the exceptions listed in the guide is diesel fired central heating systems "where the manufacturer specifies direct connection to the batteries". Does Mikuni specify this? I dunno. 

[Tony Brooks]

2 minutes ago, WotEver said:

One of the exceptions listed in the guide is diesel fired central heating systems "where the manufacturer specifies direct connection to the batteries". Does Mikuni specify this? I dunno. 

I suspected I had missed something. However assuming a competent installation the only reason I can see for that being a requirement is if the boiler needs a permanent memory supply like car radios.

[Robbo]

19 minutes ago, Tony Brooks said:

After al this I am still wondering why the Mikuni seems to be fed from the batteries rather than the master switch. I though all bar a few special exemptions, of which a heater is not one, had to be via the  switch. That looses one connection at the batteries.

What have I missed?

I think it’s because they are very picky on voltage drop.

[sharpness]

My Mikuni is direct to the batteries which means that must be what it said in the installation instructions because I installed it.

Steve

[Tony Brooks]

2 hours ago, Robbo said:

I think it’s because they are very picky on voltage drop.

Yes, probably. but that is down to poor installation and not a reason to connect straight to the batteries. By installation I mean more than juts the Mikuni wiring. It includes wiring from batteries to distribution panel and negative bus bar back to the batteries plus the master switch. It probably easier to get a working install if they say connect direct to the batteries. Says a lot about many boats' electrical systems really.