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Topic: Alternator, battery isolator replacement  (Read 264 times) previous topic - next topic

Alternator, battery isolator replacement

Good morning All
Started getting the coach ready for the pilgrimage to warmer climates. Alternator was throwing 16+v. Batteries fully charged. Would drop to 14.2 if boosted. Cleaned all connections. No change. Thinking the alternator had given up, I changed out to a new Leece-Neville 160a that I had. New one is self excited, old one was 3 wire. Wired per instructions, main cables only. In reading realised the battery isolator also needed to be changed. Bought and installed Victron Agrofet.
Now I'm not getting any charging. What have I missed ?
Thanks for any help. Ric
Previously:'66 VW Bus"Turtle 1";'65 VW Riviera Camper "Turtle 2";
';'91 VW Syncro Camper"Syn";'92 Barth 30' -"The Big Easy"
Currently: 2000 FT U270 40', #5634 -
"Le Bons Temps"; 2003 CRV
Ric & Leslie
"Laissez les bons temps rouler!"

Re: Alternator, battery isolator replacement

Reply #1 –
Quote from: Ric & Leslie –
I changed out to a new Leece-Neville 160a that I had. New one is self excited, old one was 3 wire. Wired per instructions, main cables only. In reading realised the battery isolator also needed to be changed. Bought and installed Victron Argofet.  Now I'm not getting any charging. What have I missed ?
Since your alternator is connected to the ALT (input) post on ArgoFET isolator, there is no voltage on the B+ alternator output post, so the alternator can't "self energize".  To correct this, you must connect a wire from a "hot when ignition key is ON" source to the white "ENERGIZE" terminal at top left corner of isolator.  Doing this will supply "excite" voltage to the ALT post on isolator, which will allow the alternator to "self energize".

1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Alternator, battery isolator replacement

Reply #2 –
That's the one Chuck. I'll try running a key (hot) wire to the excite terminal.
Thanks 🙏😎Ric
I'll let you know if it works.
Previously:'66 VW Bus"Turtle 1";'65 VW Riviera Camper "Turtle 2";
';'91 VW Syncro Camper"Syn";'92 Barth 30' -"The Big Easy"
Currently: 2000 FT U270 40', #5634 -
"Le Bons Temps"; 2003 CRV
Ric & Leslie
"Laissez les bons temps rouler!"

Re: Alternator, battery isolator replacement

Reply #3 –
Chuck - Success we have achieved charging!!! b^.^d
Thanks for the assist. You've saved me from a weekend of heavy drinking.
I saw the exciter wire on the diagram but it was labelled "optional ". Clearly it is not with this alternator.
Once again the forum has saved my butt.
Happy trails. Cheers Ric 8)
Previously:'66 VW Bus"Turtle 1";'65 VW Riviera Camper "Turtle 2";
';'91 VW Syncro Camper"Syn";'92 Barth 30' -"The Big Easy"
Currently: 2000 FT U270 40', #5634 -
"Le Bons Temps"; 2003 CRV
Ric & Leslie
"Laissez les bons temps rouler!"