[Goldfinger]

The old ammeter no longer works... is redundant anyway with my new(er) more sophisticated battman system that measures everything electrical anyway.

I want to remove the old metre. I understand the metre is wired in series. SO can I just unbolt the cables tabbed to either side of the metre, then just rejoin the two cable tabs together by-passing the old metre, so completing the circuit?

Thanks in advance.

 

[btrayfors]

Yeah, you can. But why not take the opportunity to renew the cable and make sure it's the proper size to get the most out of your charging setup?

Bill

 

[Goldfinger]

...why not take the opportunity to renew the cable and make sure it's the proper size to get the most out of your charging setup?

Bill

Good idea. Will have to look at the degree of difficulty routing a new line. The ammeter is mounted onto a bulk head that backs onto the engine compartment where the cabling is. But where the cables run from/to there I don't know... the batteries are close but on the other side of yet another bulk head and under the onshore charging unit. LOTS of wires.

 

[desert rat]

Do nothing until you know where the ammeter wires go. You might create some really strange problems.

 

[eherlihy]

It is likely that the wire going TO the ammeter comes directly from the alternator. The wire coming FROM the ammeter likely goes to the starter solenoid.

If this is the case, your best bet would be to REMOVE the wire entirely, and replace it with a shorter wire that goes from the alternator to the starter. You should increase the gauge (the current wire to/from the alternator is probably AWG 10) to AWG 6 (or less) when you do this.

Connecting the two ends of the existing wire will leave in place an unnecessary load on your charging system, and introduces the possibility of arcing where the two wires are joined, thereby increasing your risk of fire.

Getting rid of the ammeter is a good thing!

 

[travlin-easy]

Why not just replace it? That way you have a backup system if your primary system fails. Amp meters are not very expensive.

Gary

 

[svzephyr44]

The old ammeter no longer works... is redundant anyway with my new(er) more sophisticated battman system that measures everything electrical anyway.

I want to remove the old metre. I understand the metre is wired in series. SO can I just unbolt the cables tabbed to either side of the metre, then just rejoin the two cable tabs together by-passing the old metre, so completing the circuit?

Thanks in advance.

The simple answer is maybe.

Case 1) You have thin wires going to the ammeter. They lead back to a "Shunt." The shunt has heavy wires on both sides. You can:
a) Just disconnect the wires going to the ammeter or
b) Remove both the ammeter wires and the shunt by hooking the wires on each side of the shunt to each other.

Case 2) (Internal Shunt) You have very heavy wires going to the ammeter. Simply hook them together.

Fair winds and following seas

 

[MarkSF]

Just to explain a bit more, in some installations the alternator output goes through the ammeter. The Universals used to do this. The problem was, that they used a rather thin wire for the job, with a dubious connector in-line. All this leads to losses between the alternator, and the battery, so you don't get the charging you should.

One fix was to simply run a new, thicker wire, directly from alternator to starter +. This had the effect of making the ammeter read zero most of the time, as the charging current bypassed it. My boat had this mod.

 

[eherlihy]

Why not just replace it? That way you have a backup system if your primary system fails. Amp meters are not very expensive.

Gary

Because the in-line ammeter was a bad idea, and the shunt-type was a less bad version of the same idea. Our friends Stu Jackson and Maine Sail have discussed this at length here: Ammeters & Shunts 101

Short version: You can get better information about the health of your charging system with a volt meter (good), a coulomb-counter (better) or SmartGauge (better still).

 

[Goldfinger]

Why not just replace it? That way you have a backup system if your primary system fails. Amp meters are not very expensive.

Gary

Redundancy in this particular item isn't mission critical, and adds a complication rather than simplifying, which is what I'm trying to do.... and what eherlihy said.

 

[Goldfinger]

It is likely that the wire going TO the ammeter comes directly from the alternator. The wire coming FROM the ammeter likely goes to the starter solenoid.

Went to the boat today. A 7mm wire does indeed do directly TO the ammeter from the alternator.

BUT the wire FROM the ammeter ends up in a scary place...please see attached files.

Looking forward to more advice.

Cheers GF

 

[eherlihy]

Assuming that the wire from the ammeter is one of the two wires on that large fuse, I would want to know where the OTHER wire goes. I would also want to know what is on the other side of the fuse.

Making another assumption (I know - dangerous to ever assume anything) that you like the way that the electrical system works, other than the ammeter, you could simply take the wire off of the ammeter, and wire it to the alternator.

 

[Stu Jackson]

Went to the boat today. A 7mm wire does indeed do directly TO the ammeter from the alternator.

BUT the wire FROM the ammeter ends up in a scary place...please see attached files.

Looking forward to more advice.

Cheers GF

If you haven't yet read eh's suggested link to Ammeters & Shunts 101 yet, then why are you asking?

What's "scary?"

Pictures of wiring without wiring diagrams are useless.

The discussions of ammeters in cockpit panels and in charging systems has been discussed so many times it is almost incomprehensible that it is not yet understood by so many.

 

[Goldfinger]

Assuming that the wire from the ammeter is one of the two wires on that large fuse, I would want to know where the OTHER wire goes. I would also want to know what is on the other side of the fuse

Looks like the second wire on the alternator/ammeter side goes directly to a battery bank. The wire on the other side of the fuse seems to go to a battery switch for the house or start bank I can't tell... but some of this is deduction, actually eyeballing this would require dismantling half the boat!

Making another assumption (I know - dangerous to ever assume anything) that you like the way that the electrical system works, other than the ammeter, you could simply take the wire off of the ammeter, and wire it to the alternator.

It won't quite reach hence my original question. But reading the advice here, replacing the whole wire would be the best thing to do.

 

[Goldfinger]

If you haven't yet read eh's suggested link to Ammeters & Shunts 101 yet, then why are you asking?

I did read the link (which certainly added to my education) but is not directly relevant to my setup, since my internally shunted ammeter is NOT in the cockpit but mounted through the engine bay wall; the connections inside the engine bay extend the overall cable run from the alternator by no more than a foot.

What's "scary?"

I say "scary" because these huge fuses suggest a LOT on potential power and making a mistake here could have disastrous consequences... and this setup is beyond my experience.

Pictures of wiring without wiring diagrams are useless.

The discussions of ammeters in cockpit panels and in charging systems has been discussed so many times it is almost incomprehensible that it is not yet understood by so many.

I don't have a wiring diagram so am hoping that posting pictures, providing what info I can and asking for guidance on how to further investigate my setup will reveal all... I was assuming that is what forums are for.

If I can't be confident with the info I get here and/or discover for myself, I will just leave it and get a professional to remove the ammeter when next I have a need to have a pro on board, but this would mean I haven't advanced my knowledge of how my boat works.

 

[eherlihy]

I'd be happy to have a looksee, and trace everything for you... All you'll have to do is pay my time and travel expenses.:laugher

 

[Goldfinger]

I'd be happy to have a looksee, and trace everything for you... All you'll have to do is pay my time and travel expenses.:laugher

Sure: fly from Boston to Sydney, a couple of days; grovelling around on my boat, say 2 more days; then fly home again. Probably a week all up plus travel costs etc... I'm sure a case of beer'll cover it.

 

[mitiempo]

I did read the link (which certainly added to my education) but is not directly relevant to my setup, since my internally shunted ammeter is NOT in the cockpit but mounted through the engine bay wall; the connections inside the engine bay extend the overall cable run from the alternator by no more than a foot.

It is relevant because an internally shunted ammeter is a restriction in charging current wherever it is mounted.

 

[mitiempo]

Looks like the second wire on the alternator/ammeter side goes directly to a battery bank. The wire on the other side of the fuse seems to go to a battery switch for the house or start bank I can't tell... but some of this is deduction, actually eyeballing this would require dismantling half the boat!

With a multimeter set to continuity and a test lead you can confirm where any wire on the boat goes.

 

[Goldfinger]

With a multimeter set to continuity and a test lead you can confirm where any wire on the boat goes.

yes you're right and this might solve some of my questions. Thanks. But I can't physically see/get to where all the wires go to AND I'll need to rig a very long test lead for some of the wires, since I'll have to go AROUND bulkheads when the wire simply goes through.

I know, I know "life wasn't meant to be easy"

More update when I visit the boat again.