Charging of domestic batteries

[MtB]

1 minute ago, rowland al said:

This is what was inside the £6 package. No instructions of course, I'm going to order a short battery link to wire the shunt up In series with the domestic negative battery connection lead (I think that's where it goes although not sure why it can't be on the positive feed?!). 

Any ideas how the wires from the meter connect? I also need to work out how to extend the wires to the digital meter as it's pretty useless having it on top of the batteries. Might just use a chock block for now. 

That’s the same kit I purchased out of curiosity then found it wasn’t ‘plug and play’ due to the need to devise an electrically safe method of mounting the shunt. Not especially difficult but I CBA. 

I’m fairly sure there are wiring instructions on the eBay listing.  

[rowland al]

18 minutes ago, Mike the Boilerman said:

That’s the same kit I purchased out of curiosity then found it wasn’t ‘plug and play’ due to the need to devise an electrically safe method of mounting the shunt. Not especially difficult but I CBA. 

I’m fairly sure there are wiring instructions on the eBay listing.  

Ah, thanks Mike.

About wiring:
Red line thin: power supply+
Black line thin: power supply -
Red line (thick): PW+, measuring terminal voltage input positive
Yellow line (thick): IN+, current input
Black line thick: COM, common measuring
 

Well the yellow wire is actually thin for starters. I can see that the thin red/black cables are just 12v power supply for the meter. Not quite sure where the others go in relation to the shunt. I presume the shunt will fit either way round. 

[MtB]

On 19/11/2017 at 11:31, rowland al said:

Ah, thanks Mike.

About wiring:
Red line thin: power supply+
Black line thin: power supply -
Red line (thick): PW+, measuring terminal voltage input positive
Yellow line (thick): IN+, current input
Black line thick: COM, common measuring
 

Well the yellow wire is actually thin for starters. I can see that the thin red/black cables are just 12v power supply for the meter. Not quite sure where the others go in relation to the shunt. I presume the shunt will fit either way round. 

 

Yes the shunt is not handed, either way around will do. 

The wires on mine match the listing you quoted. Mine has a little plug with two thin wires red and black which power the unit up. This power supply would normally be the battery you are monitoring but doesn't need to be. 

The other plug on mine has three wires, yellow red and black, all thicker. The yellow and black have forked crimp terminations to fit under the two screws on the shunt. The thick red wire goes to the positive terminal of the battery being monitored. 

So when wiring up mine, the two reds and the two blacks can just be joined together.

Edited November 19, 2017 by Mike the Boilerman

[WotEver]

See pic 6 on the listing:

https://m.ebay.co.uk/itm/DC-100V-500A-Voltmeter-Ammeter-Charge-Discharge-Isolation-current-tester-12v-24v/172733947168?_mwBanner=1

The shunt on this one goes in the +ve feed. So between the battery and the isolator. Fuse the two 12V feeds to the meter. 1A will be fine. 

Edited November 19, 2017 by WotEver

[rowland al]

27 minutes ago, WotEver said:

See pic 6 on the listing:

https://m.ebay.co.uk/itm/DC-100V-500A-Voltmeter-Ammeter-Charge-Discharge-Isolation-current-tester-12v-24v/172733947168?_mwBanner=1

The shunt on this one goes in the +ve feed. So between the battery and the isolator. Fuse the two 12V feeds to the meter. 1A will be fine. 

The problem is that they haven't sent me what is in their description. My yellow wire is thin and on the same connector as the meter power wires. Still confused here (which isn't difficult).

[cereal tiller]

2 minutes ago, rowland al said:

The problem is that they haven't sent me what is in their description. My yellow wire is thin and on the same connector as the meter power wires. Still confused here (which isn't difficult).

Thin Yellow likely for Illumination, it is on my 200 AMP one.

[WotEver]

5 minutes ago, rowland al said:

The problem is that they haven't sent me what is in their description. My yellow wire is thin and on the same connector as the meter power wires. Still confused here (which isn't difficult).

Got a link to the one you bought?

[rowland al]

3 minutes ago, WotEver said:

Got a link to the one you bought?

Yes. It's this one but it seems to take forever to load up the description page. 

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F181573154529

[WotEver]

30 minutes ago, rowland al said:

Yes. It's this one but it seems to take forever to load up the description page. 

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F181573154529

Well, yours isn’t what’s pictured so they've sent you something subtly different. I suggest you wire it as per the link in post #304 above, as the pre-wired plugs you have received appear to agree with that one and not at all like your listing. Having said that, the unit in post #304 isn’t what you have either so it’s going to be a bit of an experiment. 

[rowland al]

41 minutes ago, WotEver said:

Well, yours isn’t what’s pictured so they've sent you something subtly different. I suggest you wire it as per the link in post #304 above, as the pre-wired plugs you have received appear to agree with that one and not at all like your listing. Having said that, the unit in post #304 isn’t what you have either so it’s going to be a bit of an experiment. 

In the first of those pictures the thicker red and black leads just go to crocodile connectors but no shunt shown. The diagram in another picture seems to show the thick red and black cables connecting to each side of the shunt. So I'll try that. The circular clips fitted to the ends of these 2 thicker wires seem to add to that theory. So these must be the sense wires. 

Also,  not sure where the thin yellow wire goes. It looks like it's going to the power supply in the first picture.  The diagram shows it connected to the +12v supply so could be for illumination as CT suggested. 

The diagram does seem to show the shunt on the +12v side rather than the - ve so I'll connect it in series beteeen the +12v charging feed from the alternator and the +ve battery post. 

Does that sound about right as a first guess? 

[smileypete]

2 hours ago, rowland al said:

This is what was inside the £6 package. No instructions of course, I'm going to order a short battery link to wire the shunt up In series with the domestic negative battery connection lead (I think that's where it goes although not sure why it can't be on the positive feed?!). 

Any ideas how the wires from the meter connect? I also need to work out how to extend the wires to the digital meter as it's pretty useless having it on top of the batteries. Might just use a chock block for now. 

Looks similar to the one I have at home, I expect the way to wire it would be:

    The thick red and black wires go to the shunt, red to 'upstream' side I expect.

    The thin yellow wire goes to where you want to read the voltage from.

    The thin red and black wires power the meter, so:

       The thin red wire can go to the same point as the thin yellow wire as the meter can run directly off 12v

       The thin black wire needs to go to the same point as the thick black wire ie to the shunt.

To extend wires that small one way is to use some three amp terminal block and put some small ferrules on the ends of the wires, squish them on with pliers if need be.

As mentioned there needs to be a small fuse protecting the meter and cabling, this needs to go at the point you take the red and yellow wires from.

Looks like it's one of those ones which has a couple of presets so should be calibrated at the factory, but there's no harm in checking it.

 

[rowland al]

1 hour ago, smileypete said:

Looks similar to the one I have at home, I expect the way to wire it would be:

    The thick red and black wires go to the shunt, red to 'upstream' side I expect.

    The thin yellow wire goes to where you want to read the voltage from.

    The thin red and black wires power the meter, so:

       The thin red wire can go to the same point as the thin yellow wire as the meter can run directly off 12v

       The thin black wire needs to go to the same point as the thick black wire ie to the shunt.

To extend wires that small one way is to use some three amp terminal block and put some small ferrules on the ends of the wires, squish them on with pliers if need be.

As mentioned there needs to be a small fuse protecting the meter and cabling, this needs to go at the point you take the red and yellow wires from.

Looks like it's one of those ones which has a couple of presets so should be calibrated at the factory, but there's no harm in checking it.

 

Ok, thanks for that. I'll give that a go and see what happens. 

[WotEver]

2 hours ago, smileypete said:

The thin black wire needs to go to the same point as the thick black wire ie to the shunt.

Not if he’s wiring the shunt in the +ve as per one of the diagrams. It needs to go to batt -ve 

2 hours ago, rowland al said:

I'll connect it in series beteeen the +12v charging feed from the alternator and the +ve battery post. 

Does that sound about right as a first guess?

That will show total current being supplied by the alternator as opposed to showing only the charging current going to the Batteries. To achieve the latter, all positive connections need to be removed from the battery and connected to one end of the shunt. The other end of the shunt then goes to batt +ve. 

[smileypete]

1 hour ago, WotEver said:

Not if he’s wiring the shunt in the +ve as per one of the diagrams. It needs to go to batt -ve 

That will show total current being supplied by the alternator as opposed to showing only the charging current going to the Batteries. To achieve the latter, all positive connections need to be removed from the battery and connected to one end of the shunt. The other end of the shunt then goes to batt +ve. 

Don't think it will work with the shunt in the positive. Could try if you really want...

There are now cheap ammeters that can have the shunt in the positive, as they have an isolating converter built in, like mentioned in here:

EtA: I thought the OP already had an ammeter, not sure why he's getting another one?

Edited November 19, 2017 by smileypete

[WotEver]

25 minutes ago, smileypete said:

Don't think it will work with the shunt in the positive.

See post #304. 

Its not very clear at all what he has. 

But his plugs & cables look more like the ones which connect the listing linked in 304 than they do to the ones in the listing he ordered. 

Edited November 19, 2017 by WotEver

[smileypete]

1 hour ago, WotEver said:

See post #304. 

Its not very clear at all what he has. 

But his plugs & cables look more like the ones which connect the listing linked in 304 than they do to the ones in the listing he ordered. 

It's a totally different meter to the one in post #304 (FFS! )

I'm just trying to help the guy, despite the 'expert' nitpicking. He's totally free to ignore my advice if he feels like it....

Ideally he would have bought the one in post #304, but we are where we are...

Edited November 19, 2017 by smileypete

[WotEver]

4 minutes ago, smileypete said:

It's a totally different meter to the one in post #304 (FFS! )

I'm just trying to help the guy, despite the 'expert' nitpicking. He's totally free to ignore my advice if he feels like it....

And it’s a totally different meter to the one he ordered!!  Just look at the picture! 

All any of us are trying to do is to help him and pointing out that the neg wire doesn’t go to the shunt if he puts it in the pos feed is hardly nit-picking, is it?  Why don’t you simply admit that you gave bad advice instead of trying to argue every point? 

[WotEver]

2 hours ago, WotEver said:

That will show total current being supplied by the alternator as opposed to showing only the charging current going to the Batteries. To achieve the latter, all positive connections need to be removed from the battery and connected to one end of the shunt. The other end of the shunt then goes to batt +ve. 

I guess it’s obvious that if you put the shunt on the -ve side then it’s similar advice to the above - remove ALL the negative wires from the domestic batteries and reconnect them to one side of the shunt. The other side of the shunt goes to the battery negative. 

[smileypete]

11 minutes ago, WotEver said:

And it’s a totally different meter to the one he ordered!!  Just look at the picture! 

All any of us are trying to do is to help him and pointing out that the neg wire doesn’t go to the shunt if he puts it in the pos feed is hardly nit-picking, is it?  Why don’t you simply admit that you gave bad advice instead of trying to argue every point? 

All I'm saying is that I believe the meter he purchased won't work if he tries to put the shunt in the positive, he's more than welcome to ignore my advice and try.

The diagram on the page that he purchased from only shows the shunt in the negative, so my advice relates to that situation only.

OK it's a shame that the meter he received has different colors and thicknesses for the connection wires, but that won't affect the basic operation.

If he wants to have a shunt in the positive I believe he would be better off with the meter in post #304, if so it's a pity he didn't purchase that one.

 

Maybe this is why it's good idea to just pony up £100 or so and buy a Nasa BM1 or BM2, it greatly restricts choice, which can be a bad thing if there's too much of it...

Edited November 19, 2017 by smileypete

[WotEver]

1 minute ago, smileypete said:

The diagram on the page that he purchased from only shows the shunt in the negative, so my advice relates to that situation only.

However, he hasn’t received that meter. Nor are the wires or connectors as per the description. The wires and connectors are much more like #304 but of course that doesn’t mean that the meter is anything like it in function. 

[smileypete]

9 minutes ago, WotEver said:

However, he hasn’t received that meter. Nor are the wires or connectors as per the description. The wires and connectors are much more like #304 but of course that doesn’t mean that the meter is anything like it in function. 

Correct, my advice was based on the picture of the actual meter and connections he received, as I said in post #313.

I assumed he'd want to put he shunt in the negative as that's what the ebay page that he bought off actually said.

Hopefully if he wanted to put the shunt in the positive, he wouldn't have bought one off a page that didn't say it could go in the positive, right?

Edited November 19, 2017 by smileypete

[WotEver]

1 minute ago, smileypete said:

Hopefully if he wanted to put the shunt in the positive he wouldn't have bought one off a page that didn't say it could go in the positive, surely.

Well, you would have thought so...

 

[smileypete]

Just now, WotEver said:

Well, you would have thought so...

Hopefully he'd have bought the other on you linked to in post #304, which specifically states:

Shunt can installed on the Positive or Negative side of power (Anywhere).
It can be powered by the same power being measured, no need ISOLATED power.

I think we're finally on the same page now.

In any case I feel putting the shunt in the negative is safer as any inadvertent short to hull or engine metalwork won't short the battery supply. The one in post #304 is still better than the one in post #308 as it can read current in both directions.

[WotEver]

17 minutes ago, smileypete said:

The one in post #304 is still better than the one in post #308 as it can read current in both directions.

Yup. I originally posted that link in post #78 and then in post #113 OP said that he’d ordered one. Sadly he ordered a different one. 

[rowland al]

20 minutes ago, WotEver said:

Yup. I originally posted that link in post #78 and then in post #113 OP said that he’d ordered one. Sadly he ordered a different one. 

You are probably right about that. But to confuse things, I did get something I didn't order. Maybe it's better?!