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A Lot of Motors / charging systems, have to be bumped..... up to {About} 1200 RPM to excite the alternator.

BOAT wrote:what's "the bump" ?

I think people overestimate alternator charge capacity frequently.

My Merc 50 has a 200 watt output alternator, or about 15 amps at 13-14 Volts. I'm guessing 5 amps is used by the engine for fuel pump and EFI. At idle I'm guessing only 1-2amps is available for battery charging.

The place to use bonded to boat solar is the black stripe. It gets great exposure all day. The forward part of the black stripe on the M should be enough for average use. Plus it would look very clean.
Ix

FYI, from the Amazon link:

Question: Do the panels have a protective outer layer? I'm thinking about mounting the 120w version on a boat where it would be stepped on on an once in a while
Answer: No, it can not be stepped on. It can only be waterproof.
By KINGSOLAR on July 14, 2015

mastreb tested the charging ability of the etec 60 and it was pretty incredible - I don't remember the numbers but they are here on the site somewhere and he had the etec 60 putting out an incredible amount of electricity at idle. as i recall in that post there were people that were actually talking about running a microwave off the etec 60 at idle to warm up their popcorn or something like that.

we should find that post.

Sea Wind wrote:FYI, from the Amazon link:

Question: Do the panels have a protective outer layer? I'm thinking about mounting the 120w version on a boat where it would be stepped on on an once in a while
Answer: No, it can not be stepped on. It can only be waterproof.
By KINGSOLAR on July 14, 2015

With them bonded down good so there is no flex when stepped on, I am not concerned about stepping on them In my bare feet or deck shoes. I will make sure next time I have a stripper on the boat using the mast as a pole I will have her take her stripper heels off.



Not the same manufacturer but the same construction style. Once again not worried about stepping on them! Of course there is realy no stress on the panel in that picture.

i CAN'T WAIT TILL THEY PAVE ALL THE ROADS IN THE WORLD WITH SOLAR PANELS AND THEN WE WILL HAVE FREE ELECTRICITY FOR EVERYONE! (yay!)

Funny thing about humans... The more there is of something the more they will use. IE need rises with production and lowered costs. It's a law I think. If electricity was free the usage woukd always be a bit more then the capacity to make it.
The solar road idea is a good one and could power a car and also charge its batteries for use on non electrified roads. They could begin to electrify the roads now, using power lines near to the roads. Leave the oil for heavy trucks. Never happen though.
Ix

E-tec claims on their site 81 Amps 1100 watts.... Mercury claims 68 Amps with no wattage claim on their site that I could find. Can we agree that watts = volts x amps? @ 12 volts its 972 watts for Etec and 816 for Merc. Both alternators are computer controlled but I have no idea what that really offers us. At what RPM must you run the motor to get what amp/wattage numbers are SECRETS hahaahaahaha

BOAT wrote:mastreb tested the charging ability of the etec 60 and it was pretty incredible - I don't remember the numbers but they are here on the site somewhere and he had the etec 60 putting out an incredible amount of electricity at idle. as i recall in that post there were people that were actually talking about running a microwave off the etec 60 at idle to warm up their popcorn or something like that.

we should find that post.

More like 14V, since it has to be high enough to charge the batt(s). And yes, it's DC, so no other parameters involved (like power factor in AC, with reactive loads).

Some of that current is used internally to run the systems, so some manufacturer's publish a 'net' figure, usually along with the larger gross figure. Though I'm always a little suspicious of big current claims, as the typical alternator on an inboard is in the 50-70A range, and those are physically large units.

well, mastreb said the etec 60 put out a lot of power at idle and he checked it - so THERE!

The etec 60 specsheet says 81A total, & 25A for charging

http://www.cangarmotors.com/wp-content/ ... -60-HP.pdf

Online etec owners say
500 rpm - 1 amp
1000 rpm - 9 amps
1500 rpm - 12 amps
2000 rpms - 14 amps
2500 rpms - 22 amps
3000 and up - 25 amps

I have read the DI 2 strokes need a higher RPM to build the charging amps since it takes so much power to run their systems. The optimax will actually drain the batteries at idle.

Suzuki posts their output for the 90/115, Its climbs pretty quickly,


I had a shunt & amp meter on my DF90 and found the graph accurate, I woudl get 35A at 1000 rpm. It spoiled me, Just a little motoring each day on a trip and the bulk of the juice was back.


Yamaha has a similar curve.

Seapup wrote:The etec 60 specsheet says 81A total, & 25A for charging

http://www.cangarmotors.com/wp-content/ ... -60-HP.pdf

Online etec owners say
500 rpm - 1 amp
1000 rpm - 9 amps
1500 rpm - 12 amps
2000 rpms - 14 amps
2500 rpms - 22 amps
3000 and up - 25 amps

I have read the DI 2 strokes need a higher RPM to build the charging amps since it takes so much power to run their systems. The optimax will actually drain the batteries at idle.

Suzuki posts their output for the 90/115, Its climbs pretty quickly,


I had a shunt & amp meter on my DF90 and found the graph accurate, I woudl get 35A at 1000 rpm. It spoiled me, Just a little motoring each day on a trip and the bulk of the juice was back.


Yamaha has a similar curve.

Remember output capacity and charge ability are two different things. You will not charge the battery at full output unless it is almost completely dead. The alternator is a constant voltage charger not constant current.

Well I just checked the service Manual Mercury 60HP EFI

Output at 1000 rpm: 12.5A
Output at 5000 rpm: 17.5

BUT to mesure would be even more realistic.
How about the following method: Just put more and more load at a 12V plug. When the watts gets under 13.5Volts you have the limit for the actual rpm.

Correct or not?

kurz wrote:Well I just checked the service Manual Mercury 60HP EFI

Output at 1000 rpm: 12.5A
Output at 5000 rpm: 17.5

BUT to mesure would be even more realistic.
How about the following method: Just put more and more load at a 12V plug. When the watts gets under 13.5Volts you have the limit for the actual rpm.

Correct or not?

My guess is like most everything else advertized numbers would be around 12V.