On Sat, 01 Dec 2007 07:43:08 +0700, Bruce in Bangkok
wrote:

On Fri, 30 Nov 2007 21:08:04 GMT, (Richard
Casady) wrote:

On Tue, 16 Oct 2007 13:30:16 -0700, Tim wrote:

I've seen many a 130A L/N come in with stators fried to a crisp due to
rotten batteries and/or dubious ground cables. (but usually the pos.
rectifier was toast too!)

I have seen many a fusable link in an alternator output wire. How do
you fry electrical goods with a proper fuse in place? You don't. I
thought there was a voltage regulator. That doesn't protect the
alternator?

Casady

No, the normal alternator regulator simply controls the output of the
alternator in reference to battery voltage. Low battery voltage high
output, high voltage low output.

It must not be so simple/cheap to regulate current, or they would
probably do it. They do put in that dirt cheap fusable link.

Casady

"Richard Casady" wrote:

It must not be so simple/cheap to regulate current, or they would
probably do it. They do put in that dirt cheap fusable link.

Just takes money AKA: Larger conductors, AKA: More copper.

Using system voltage to control field current (usually no more than 5Amps),
thus controlling alternator output, is very straight forward.

If a bad battery, or a defective cable, wipes out an alternator, that's not
the alternator's fault, that's a system problem, IMHO.

Lew

On Sat, 01 Dec 2007 13:35:16 GMT, (Richard
Casady) wrote:

On Sat, 01 Dec 2007 07:43:08 +0700, Bruce in Bangkok
wrote:

On Fri, 30 Nov 2007 21:08:04 GMT, (Richard
Casady) wrote:

On Tue, 16 Oct 2007 13:30:16 -0700, Tim wrote:

I've seen many a 130A L/N come in with stators fried to a crisp due to
rotten batteries and/or dubious ground cables. (but usually the pos.
rectifier was toast too!)

I have seen many a fusable link in an alternator output wire. How do
you fry electrical goods with a proper fuse in place? You don't. I
thought there was a voltage regulator. That doesn't protect the
alternator?

Casady

No, the normal alternator regulator simply controls the output of the
alternator in reference to battery voltage. Low battery voltage high
output, high voltage low output.

It must not be so simple/cheap to regulate current, or they would
probably do it. They do put in that dirt cheap fusable link.

Casady

Remember that alternators are designed as a part of a system. Not,
perhaps specifically for a Ford FX-1000 - whatever, but for an
electrical system using approximately a 50 AH battery, system voltage
nominal 12 VDC and engine RPM of 4,000 RPM.

So the alternator guy knows maximum amps, volts and pulley size and he
can design or select the proper unit to fit the needs of the user.

It would be practical to measure amperage but it would increase the
cost of the alternator and none of the Cheap Charley boaters would buy
one. :-)


Bruce-in-Bangkok
(Note:remove underscores
from address for reply)