On Wed, 23 Jun 2004 08:50:10 -0400, "Doug Dotson"
wrote:

You can go up to a 160 amp alternator without having to
resort to a large frame dual belt model.

========================================

Doug, can you cite some references on that? I've never heard of
anyone recommending 100+ amps without dual belts. I used to run a 120
amp Balmar on one of my old sailboats with a single belt. Frankly it
left a lot to be desired even at 50 to 60 amps - lots of squealing and
chewed up belts. It would never get even remotely close to 100 amps,
even for short periods. The belt slip was just too much for it.

In article ,
Wayne.B wrote:

Doug, can you cite some references on that? I've never heard of
anyone recommending 100+ amps without dual belts. I used to run a 120
amp Balmar on one of my old sailboats with a single belt. Frankly it
left a lot to be desired even at 50 to 60 amps - lots of squealing and
chewed up belts. It would never get even remotely close to 100 amps,
even for short periods. The belt slip was just too much for it.

Ok here we go with the Math...... 120 amps @ 13.6Vdc = 1632 Watts
figure that you alternator is say, oh 75% efficent that equals
2175 watts of input energy, which equals 2.916 Horespower.
Now 3 HP thru one belt? Well, it can be done with a C size belt, but
most engineering folks like to spec max 1.5 HP per belt.

So two belts would be prefferable for 3 HP worth of work.

The above assumes Vbelts, and not gear-belts which can easily
handle up to 6 HP with no problems.


There are belts and there are Belts, so lets get the definitions
set down first......


Bruce in alaska who is running a 6 HP air compressor on a 2.5
inch gearbelt off my 4-108 Perkins 10Kw genset
--
add a 2 before @

All I can cite is the fact that I have run a 160 amp alternator
on a single belt for about 4 years. No slip, no squeel, and
full output when needed. No problems with bearings and
still on the original belt, although I have a couple of spare
belts due to the heavier stress expected. Very happy so
far. I would use a dual belt unit if my space would allow it.

Doug
s/v Callista

"Wayne.B" wrote in message
news
On Wed, 23 Jun 2004 08:50:10 -0400, "Doug Dotson"
wrote:

You can go up to a 160 amp alternator without having to
resort to a large frame dual belt model.

========================================

Doug, can you cite some references on that? I've never heard of
anyone recommending 100+ amps without dual belts. I used to run a 120
amp Balmar on one of my old sailboats with a single belt. Frankly it
left a lot to be desired even at 50 to 60 amps - lots of squealing and
chewed up belts. It would never get even remotely close to 100 amps,
even for short periods. The belt slip was just too much for it.

How many amps do you actually get from the alternator, and how big is your
battery bank? I have a 100 Amp alternator, but it hardly ever does more than 84
Amps into a 425 AH bank.




"Doug Dotson" wrote in message
...
All I can cite is the fact that I have run a 160 amp alternator
on a single belt for about 4 years. No slip, no squeel, and
full output when needed. No problems with bearings and
still on the original belt, although I have a couple of spare
belts due to the heavier stress expected. Very happy so
far. I would use a dual belt unit if my space would allow it.

Doug
s/v Callista

"Wayne.B" wrote in message
news
On Wed, 23 Jun 2004 08:50:10 -0400, "Doug Dotson"
wrote:

You can go up to a 160 amp alternator without having to
resort to a large frame dual belt model.

========================================

Doug, can you cite some references on that? I've never heard of
anyone recommending 100+ amps without dual belts. I used to run a 120
amp Balmar on one of my old sailboats with a single belt. Frankly it
left a lot to be desired even at 50 to 60 amps - lots of squealing and
chewed up belts. It would never get even remotely close to 100 amps,
even for short periods. The belt slip was just too much for it.

Battery bank is just under 600AH. Alternator is rated 160A cold,
but 147A hot which is the actual useful output. I've seen it put
out as much as 120A, but that was on purpose to test it out. I don't
normally let the batteries get low enough to require such high
currents. Normally charge using the genset to power a 110A
shorepower charger.

Doug
s/v Callista

"Jeff Morris" wrote in message
...
How many amps do you actually get from the alternator, and how big is your
battery bank? I have a 100 Amp alternator, but it hardly ever does more
than 84
Amps into a 425 AH bank.




"Doug Dotson" wrote in message
...
All I can cite is the fact that I have run a 160 amp alternator
on a single belt for about 4 years. No slip, no squeel, and
full output when needed. No problems with bearings and
still on the original belt, although I have a couple of spare
belts due to the heavier stress expected. Very happy so
far. I would use a dual belt unit if my space would allow it.

Doug
s/v Callista

"Wayne.B" wrote in message
news
On Wed, 23 Jun 2004 08:50:10 -0400, "Doug Dotson"
wrote:

You can go up to a 160 amp alternator without having to
resort to a large frame dual belt model.

========================================

Doug, can you cite some references on that? I've never heard of
anyone recommending 100+ amps without dual belts. I used to run a 120
amp Balmar on one of my old sailboats with a single belt. Frankly it
left a lot to be desired even at 50 to 60 amps - lots of squealing and
chewed up belts. It would never get even remotely close to 100 amps,
even for short periods. The belt slip was just too much for it.

On Wed, 23 Jun 2004 23:33:42 -0400, "Doug Dotson"
wrote:

All I can cite is the fact that I have run a 160 amp alternator
on a single belt for about 4 years. No slip, no squeel, and
full output when needed.

===================================

What kind of alternator and what kind of belt?

Alternator is a PowerTap PT59. Can;t remember the specifics
about the belt but I seem to recall it is a Goodyear that I had
to special order from Canada. Not that the type of belt was unusual
but the length was for some reason. I ordered 4 so I would always
have some spares.

Doug
s/v Callista

"Wayne.B" wrote in message
...
On Wed, 23 Jun 2004 23:33:42 -0400, "Doug Dotson"
wrote:

All I can cite is the fact that I have run a 160 amp alternator
on a single belt for about 4 years. No slip, no squeel, and
full output when needed.

===================================

What kind of alternator and what kind of belt?

Wayne.B wrote in
news
On Wed, 23 Jun 2004 08:50:10 -0400, "Doug Dotson"
wrote:

You can go up to a 160 amp alternator without having to
resort to a large frame dual belt model.

========================================

Doug, can you cite some references on that? I've never heard of
anyone recommending 100+ amps without dual belts. I used to run a 120
amp Balmar on one of my old sailboats with a single belt. Frankly it
left a lot to be desired even at 50 to 60 amps - lots of squealing and
chewed up belts. It would never get even remotely close to 100 amps,
even for short periods. The belt slip was just too much for it.



Lionheart's big alternator has only one belt on the alternator's crooked
pulley. It only draws 100+ amps for a few minutes, so if you keep the belt
tight it's fine.

Why does everyone think a 200A alternator is going to charge house
batteries at full current for 20 minutes and end up with a fully-charged
set of house batteries? That's CRAZY! The amount of current it will draw
has NOTHING to do with the peak current an alternator puts out. The
alternator puts out its rated output until the battery voltage rises
somewhere near the regulator's set voltage, then the current drops
DRASTICALLY to a more sane level to safely charge the plates. A surface
charge quickly raises the voltage, then the real charging begins SLOWLY
creating the chemical reaction, we hope, that recovers most of the lead
sulphate in solution back to lead plates before it crystalizes and falls
into the bilge of the battery.

Your boat can no more fully charge your boat battery at really high
currents than your local garage can fully charge your car battery in 20
minutes. It's just a SURFACE charge! To fully charge the house batteries
takes HOURS of SLOW charging to re-plate the lead which takes TIME!!

Sorry......

Larry

The funniest thing at any marina is a boater with a new 4KW inverter
carrying his electric heater down the dock with a big smile on his face.

On Fri, 25 Jun 2004 11:11:47 -0000, Larry W4CSC
wrote:
To fully charge the house batteries
takes HOURS of SLOW charging to re-plate the lead which takes TIME!!

==========================================

That's true for a 100% full charge, but a more typical recharge going
from 50% up to 75%, only takes a little over an hour with a high
output charging system.

I agree - the affect Larry describes happens, but is not that pronounced. My
system (4 6-Volt golf bats, 100 Amp Balmar, Link 2000R) charges initially at a
bit over 80 Amps, but spends about an hour gradually dropping through the 70's.
When the charge rate goes under 70 Amps, the bank is at about 80%.


"Wayne.B" wrote in message
...
On Fri, 25 Jun 2004 11:11:47 -0000, Larry W4CSC
wrote:
To fully charge the house batteries
takes HOURS of SLOW charging to re-plate the lead which takes TIME!!

==========================================

That's true for a 100% full charge, but a more typical recharge going
from 50% up to 75%, only takes a little over an hour with a high
output charging system.