Simple Solar For A Simpleton

[Ex-Calif]

Originally Posted by VirtualVagabond

While charging tonight the Amps reading was 75.

From minus 13 to positive 75 you could have a 90 amp charger on the genset.

The 5-6 hour recharge still sorta holds water for 360 amp/day. Which is a ton of consumption BTW...

[DeepFrz]

I would still like to know why the alternator is hot when its not being used...

If you have a short in the alternator you should be able to clamp your ammeter around the alternator cable (+) while you are charging from the generator. If you get a reading then you have a short in the alternator and that could be eating up your power.

[atoll]

PPS - Just back of the envelope here - If your "standing load" is 13.2 amps that's about 320 amp/day - add a little bigger load for night time due to lights and you could be pulling out 350-360amp/day. If you are running the generator for 6 hours the genny is putting about 60 amps out to fill it back up. 60 X 6 = 360

quote ex-calif

@75 amps plus 13= 88 amps fast charge,that means the charger is doing what it is supposed to do after the initial 100amp boost that the out back charger is rated at.

the spec gravities do sound normal"ish",for partially charged cells,the good thing being that they are all the same,which indicates no dead cells.

with that amount of usage,4x 8amp(100w) solar panels are going to be insufficient to meet your power demands,underway you can add another 8-10 amps per hour for the auto pilot and radar,plotter!

this brings your daily needs to around 500 ah!
that would mean you need 8 x 8(100w) amp solar panels to keep up with demand,and very sunny days.

you need to address the consuption of power if you want to be free from running that genset

[atoll]

Originally Posted by Ex-Calif

From minus 13 to positive 75 you could have a 90 amp charger on the genset.

The 5-6 hour recharge still sorta holds water for 360 amp/day. Which is a ton of consumption BTW...

the outback charger is rated at 100 amps contniuos.

[Nicholson58]

Do yourself a favor and look up and read through Handy Bob's blog. He has done what we all desire for our boats but on motor homes. He has very frank opinions regarding some of the suppliers. Especially pay attention to the favored charge controller, the wire sizing and length. Also, Bob recommends a particular small inverter for small AC needs. Solar panel efficiency is markedly improved in the last couple of years. The cheap panels are around 10 to 12 % and the good ones are up around 18 to 22%. We bought 660 watts of Sanyo high voltage panels. Operate in parallel and use an MPPT charge controler. Our batteries are total 900 AH of LIFELINE AGM. Lifeline can ship factory direct for way better than local retail.

Other comments regarding getting control of your power consumtion are spot on. We replaced all 60 IC lights in all fixtures including NAV with PWM LED's. Our chart plotter & radar were both junk. New Simrad NSE-8 and Broadband radar - both vast improvements in technology and way lower power use.

https://handybobsolar.wordpress.com/

[atoll]

Originally Posted by DeepFrz

I would still like to know why the alternator is hot when its not being used...

If you have a short in the alternator you should be able to clamp your ammeter around the alternator cable (+) while you are charging from the generator. If you get a reading then you have a short in the alternator and that could be eating up your power.

i agree on this as well,most marine fridge units cycle at 4-6 amps,,even running a water cooling pump is only going to draw 2-3 amps

ps have you tried switching everything off at the dc distubution panel,and then reading the xantrex for amps going out?

[cwyckham]

The suspense is killing me. Where is all your juice going? Have you explored the alternator issue yet? What is your load when you shut everything off? Do you still have a big drain going somewhere else?

[Dsanduril]

The suspense is killing me. Where is all your juice going? Have you explored the alternator issue yet? What is your load when you shut everything off? Do you still have a big drain going somewhere else?

+1

I agree with everyone else, the draw and the amount of charging all seem to work out properly. It looks like you are taking out and putting in about the same amount every day. And, at 75A the charger is doing OK, with another -13 still going out that works out to 88A output, which is in the right ballpark.

So, the question of the hour is whether that 13A is useful or parasitic. Time to start disconnecting things and see what happens. Since you said the alternator was hot I would start there. As posted earlier, the field current can be 5-6A. The other option is a blown rectification diode. Usually those blow open, but not unheard of for them to short. Either amp clamp each wire or disconnect all wires one at a time. Make sure you mark where they go Don't run the engine until they are all hooked back up properly again.

[Nicholson58]

Originally Posted by Dsanduril

+1

I agree with everyone else, the draw and the amount of charging all seem to work out properly. It looks like you are taking out and putting in about the same amount every day. And, at 75A the charger is doing OK, with another -13 still going out that works out to 88A output, which is in the right ballpark.

So, the question of the hour is whether that 13A is useful or parasitic. Time to start disconnecting things and see what happens. Since you said the alternator was hot I would start there. As posted earlier, the field current can be 5-6A. The other option is a blown rectification diode. Usually those blow open, but not unheard of for them to short. Either amp clamp each wire or disconnect all wires one at a time. Make sure you mark where they go Don't run the engine until they are all hooked back up properly again.

I found a persistant draw on our system that turned out to be the Xantrex PATHMAKER. This is a battery combiner with a computor modual. The solenoid to the main contactor was commanded to be energized at all times. Also, I have found that the parasitic losses due to the powering of the ignition circuits is one of the biggest power draws on the boat.

[Dsanduril]

I have found that the parasitic losses due to the powering of the ignition circuits is one of the biggest power draws on the boat

Do you need the ignition circuits on all the time?

This would explain the warm alternator. Generally the alternator field current is routed through the ignition switch, that way it is only running when the ignition switch is on, which usually means the engine is running.

If, for some reason you need/want the ignition circuits on then check the draw at the alternator, then turn off the ignition and see if that drops. If it does, you could add a separate switch in the field line that could be turned on only when you want to run the engine.

Also, if the combiner is connecting the starting battery to the house battery then that would explain why ignition power would get drained from the house system (it should normally come from the starting battery, which would quickly be dead if not for the combiner).

[VirtualVagabond]

Ok...
I have a brand new Radio Shack clamp multi-meter in my hot little hands.
Today I will be going through a bunch of the suggestions and seeing what readings I get.
It's good to know that the basic system seems ok with the figures more or less making sense and we're back to the question of why the high consumption?
I disconnected the alternator yesterday, but I'll connect it back up to take the readings, genny on and genny off etc.
Thanks for all the support

[atoll]

pay attention to the outback charger/ inverter as well,which even when a/c switched off is still connected to the dc wiring.
best of luck!

[VirtualVagabond]

Originally Posted by atoll

pay attention to the outback charger/ inverter as well,which even when a/c switched off is still connected to the dc wiring.
best of luck!

Thanks,
Will do.

[DeepFrz]

And you thought this was going to be simple...

[VirtualVagabond]

Originally Posted by DeepFrz

I would still like to know why the alternator is hot when its not being used...

If you have a short in the alternator you should be able to clamp your ammeter around the alternator cable (+) while you are charging from the generator. If you get a reading then you have a short in the alternator and that could be eating up your power.

Ok... the reading off the + alternator lead is 1.59 to 1.78 amps with the genny off.
With the genny running and the inv/charger off, 1.59 amps
With the genny running and the inv/charger on, 1.08 amps

Does this indicate a short?