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Re: Exciting the alternator?

Posted: Mon Feb 20, 2017 9:26 pm
by Marc
Even a tiny wire from that ground screw on the housing to the chassis will make it pass an ohmmeter test so you must do an active voltage-drop test under load (headlights, etc. all on) between the alternator housing and chassis ground. If it fails, check again between the housing and the pedestal to see if it's just due to the painted housing. If the main grounding point where the alternator housing contacts the saddle has high resistance, that little wire will take more of the current and quickly go up in smoke. The ground path must be capable of handling the rated output of the alternator (~55A for a stock one).

Re: Exciting the alternator?

Posted: Sun Mar 25, 2018 7:39 am
by Reggie
Hello,
About Exciting the alternator, I have a 36V 72A automobile alternator, I needed to use it for charging of banks of Batteries only, when I connected the Alternator to AC motor to get the needed rpm of the Alternator. my question is, do I need to connect a 36V Idiot light instead of the 12v Idiot light, considering I am charging a 36V battery bank?

Re: Exciting the alternator?

Posted: Fri Mar 30, 2018 8:30 am
by Dale M.
Reggie wrote:
Sun Mar 25, 2018 7:39 am
Hello,
About Exciting the alternator, I have a 36V 72A automobile alternator, I needed to use it for charging of banks of Batteries only, when I connected the Alternator to AC motor to get the needed rpm of the Alternator. my question is, do I need to connect a 36V Idiot light instead of the 12v Idiot light, considering I am charging a 36V battery bank?
IF you are using electric motor to run an alternator to charge batteries I would really consider using AC to DC converter and skip the mechanical stuff, I know you already have invested in motor and alternator............ Other then that.... You probably need a 36Volt lamp to use it the excitation circuit for alternator if its a two wire alternator( with B+ & D+) ...

You can maybe use different technology, but I'm not sure where you will find a 36V LED...

Image

Probably would not need "anti-run on diode" in this scenerio...

Dale

Re: Exciting the alternator?

Posted: Tue Apr 03, 2018 7:03 am
by Reggie
Thanks Dale, I already have a 36V LED Lamp to use as IDIOT LAMP. My question is, do I need the Anti-Run diode and the fuse? Cant i just connect the 36V IDIOT LAMP from the D+ to the alternator positive without the need of the fuse and the Anti-Run On Diode, and easily excite the 36V alternator? Thanks once more.

Re: Exciting the alternator?

Posted: Thu Apr 05, 2018 11:39 am
by Piledriver
A modern 36v alt may not need an external exciter etc, I don't think anyone here is familiar with it.
What is it from? model#?

It is unlikely to be the same as a 1970s vw alternator.

What are you using for a starter?
(just running off one bank?)

Without that info everyone is guessing.

Re: Exciting the alternator?

Posted: Fri Apr 06, 2018 9:03 am
by Dale M.
Reggie wrote:
Tue Apr 03, 2018 7:03 am
Thanks Dale, I already have a 36V LED Lamp to use as IDIOT LAMP. My question is, do I need the Anti-Run diode and the fuse? Cant i just connect the 36V IDIOT LAMP from the D+ to the alternator positive without the need of the fuse and the Anti-Run On Diode, and easily excite the 36V alternator? Thanks once more.
NO on anti run on diode... IT is in circuit for automobile application where voltage bleed through idiot lamp may cause enough voltage to flow to coil to keep car running when key is turned off...

Is this 36 volt system for vehicle use or battery charging for battery bank of something like off the grid or electric vehicle or???

Dale

Re: Exciting the alternator?

Posted: Mon Apr 16, 2018 2:47 pm
by Reggie
Thanks Dale, the 36V system is for battery bank charging. Thanks.