ABYC Standards

[Mo]

Thanks

Hi Neil and others...thanks! So, along with the facts you've come up with I have a couple of screw ups of my own to add in the mix. And that shop vac you pictured is the exact one. Pics attached;
...battery (2 like you see in this pic) and
...wire to converter....

-My wire is not heavy enough
- the wire is approximately 3 feet long....pics attached.

I only use it to suck up cookie crumbs and inflate the dinghy. That little shop vac will inflate and deflate a dinghy quick. I usually have to break it out after a weekend on the boat.

Computer charging, phone charging, computer operation, dvd player operation and Sirius Satellite radio all plug in and do fine.

[ndutton]

Don't beat yourself up on the installation. I bet there was virtually nothing mentioned in the inverter literature about what we're talking about here. Everything I found on inverters conveniently left out input amperage.

Wait till you try attaching #2 wire to the inverter. Chances are the terminals aren't big enough.

Just how important is this vacuum?? Cookie crumbs you say? How 'bout a SCUBA tank to inflate the dink? I used to drive south of Ensenada with a group to dive and that's what we did, brought an extra tank to blow up the Zodiac, topped it off with the foot pump.

[Mo]

Neil,
I can upgrade the wiring fairly easy I think...might have to get the ends done to fit...maybe Maritime Battery can do that, they make up all kinds of items.

My wife says that if I was as neat as home as I am on the boat I "would have potential". The vacc is not a big deal and it works fine with the engine running / alternator putting out .... I suppose I COULD sweep

[joe_db]

The SSB is 100 watts RF output and the 2 meter is 65 watts RF output. The draw when receiving is more like 1 amp.

Joe:

It was the amps quoted for the radios that befuddled me.

Bill

[joe_db]

Refrigeration has to run 24/7. I can wait to vacuum for shore power or when the engine is running

I don't know that the following observation includes you Shop Vac guys but it's interesting there's a general aversion to refrigeration because of power consumption but a vacuum that hammers the living Hell out of a battery is OK?
.

[ndutton]

I can wait to vacuum for shore power or when the engine is running

Even with the engine running what size alternator do you have to compensate for an 83 amp load and what's it's effective output at 2000 RPM? My 100 amp alternator dyno'ed at 50 amps @ 2000 RPM. That assumes a flat battery bank connected. A reasonable residual charge in the bank and the alt output will be less.

Refrigeration has to run 24/7.

During periods when the boat is not in use and/or away from shore power as in the case of a mooring there's always an 'off' switch on refrigeration too. It can be reserved for weekends or cruises. It all depends on power management strategies, same as vacuuming.

I wasn't saying one is better or worse than the other. They're both heavy hitters when it comes to power consumption but much like the gas/diesel tug of war, refrigeration is often disdained while other heavy loads aren't.

[joe_db]

I used to sell and install marine reefers. I *know* my present system is not up to it without a lot of engine runtime.
BTW - I just did a little vacuuming and I saw - 6 amps when it was on, so I guess I got 44 amps out of the alternator. (50 amps total draw)

Even with the engine running what size alternator do you have to compensate for an 83 amp load and what's it's effective output at 2000 RPM? My 100 amp alternator dyno'ed at 50 amps @ 2000 RPM. That assumes a flat battery bank connected. A reasonable residual charge in the bank and the alt output will be less.

During periods when the boat is not in use and/or away from shore power as in the case of a mooring there's always an 'off' switch on refrigeration too. It can be reserved for weekends or cruises. It all depends on power management strategies, same as vacuuming.

I wasn't saying one is better or worse than the other. They're both heavy hitters when it comes to power consumption but much like the gas/diesel tug of war, refrigeration is often disdained while other heavy loads aren't.

[edwardc]

With motors, there's an additional factor to consider.

The start-up surge when turning on a motor can briefly be many times the steady-state rating of the motor. It's short enough that it doesn't always blow the breaker, but it's hell on the inverter. An electrician told me that when using an inverter to run a motor, as a rule-of-thumb the inverter's rating should be six times the motor's rating to prevent early failure of the inverter!