Charging devices playing together?

[Extemporaneous]

For instance:
If I'm plugged into shore power and my AC charger is charging my batteries, what happens if I start my engine (without unplugging my shore power) and my high output alternator goes online?
Do I need to do something or install something in order that I avoid fights in the playground? Or do they just inherently work together and how would that be exactly? Do you get the sum of the charging amps of the two systems working for you or does one stop charging because the other has the apparent voltage bumped up and the other does not think a charge is needed?

I hate electricity!
It's tough being so ignorant.
Thanks for any help you can give.

Extemp.

[scotte]

Kind of depends on how it's all wired.

For example, on my boat the engines starting battery is on the echo charge of the battery charger. The sense wires for the engine alternator external voltage regulators are on the house bank - and charge both via battery isolators. So in my case, this means that the alternators won't charge the engine battery if the shore charger is on and the house batteries are charged. Not much of an issue in my case...

[Extemporaneous]

I'll have to do some more work on this one.

Thanks,
Extemp.

[David M]

You don't have to do anything. They wont "fight" each other. All a charger knows is the systems voltage. It will regulate the current or whats sometimes called "amperage", until the voltage comes up to the level that the charger or alternator was designed to bring the voltage up to. Basically, DC sources regulate voltage by either increasing or decreasing the current (in Amps) they produce.

If you have more than one source of DC, which you do. As the system voltage rises, the DC sources with the lower maximum voltage settings, will start cutting back their current flow. When the system voltage exceeds their maximum voltage output, they will cut their current output to zero or near zero. The DC source with the highest maximum voltage setting will be the one remaining device that is keeping your system voltage at its present voltage level.

None of your DC sources will ever have exactly the same maximum voltage or produce the same current at the same RPM(as applied to alternators)....even if the specs say they do. I have two identical alternators which charge the same circuit and even when run at the same speed, they never produce the same exact current. I have two digital ammeters, one for each alternator, where I can read each alternators current output. My two chargers never produce the same current at the same system voltage.

There are smart three stage chargers, but you will do no harm to them by running the engines alternator while they are on. Alternately, the three stage charger(s) will not damage your alternator(s) while they are turning. You're three stage chargers just wont be able to do their three stage function while the alternators are turning, which won't hurt either the alternator or the charger.

I start my engines all the time while connected to shore power with both battery chargers on. There have never been any problems in doing this. I have two chargers and two alternators...all four sources of DC been operating at the same time with no ill effects.

Unlike some siblings, my four DC sources get along just fine 100% of the time.

Its AC where you will have major problems if you every try combining two different AC sources...like your shore power with your AC genset or with you're inverter...or try combining any combination of the three sources. Combining AC sources can be done with the right equipment by matching the wave form, but how that is done would be going outside the scope of your question since yours is a question about DC.

[Extemporaneous]

Originally Posted by David M

Its AC where you will have major problems if you every try combining two different AC sources...like your shore power with your AC genset or with you're inverter...or try combining any combination of the three sources. Combining AC sources can be done with the right equipment by matching the wave form, but how that is done would be going outside the scope of your question since yours is a question about DC.

Thanks David, that makes me feel better. I'm not sure how much more of this electrical stuff I can grasp.
Regarding combining DC sources, see some Q & A with Victron below.
Victron looks like pretty nice stuff. I hope it IS as I just ordered one of their muti tap Isolation transformers.
Regards,
Extemp.

To: Victron
Subject: A Power Assist Question for the Phoenix MultiPlus

Hello,
Below is from the Victron Energy Web Site.
Under the Inverter Section of the Specification for the Phoenix MultiPlus it says that the output will be a 60Hz.
When used in conjunction with your Isolation Trans. 3600W 115/230V (Model # ITR040362040) and with it plugged into European 230v and outputting 120v, I assume that the 120v would still be at 50Hz. If indeed this is true (please confirm) then what would happen if through the Inverter, the power assist engaged, but outputting at 60Hz?
I understand that note (1) in the spec below says that you can change it to 50Hz output manually, but If one forgot to do that, what would happen?
Please let me know.
Regards.

The inverter frequency will follow what the input frequency is. If you are plugged into a 230 50 Hz shore cord, your isolation transformer can change the voltage to 120 50 Hz. The Multi, while programmed for 60 on the inverter, will sense the 50 Hz and produce 50 Hz while shore power is present. When shore power is interrupted it will switch back to 60 Hz.

Regards,

Victron

[David M]

Extemp,
I'm sorry, I don't understand the question. Could you describe in more detail what you want to do?

I'm not familiar with Victron so I don't have any opinion of them. Different types of inverters that change between 50 and 60 Hertz are beyond the scope of what I know. Hopefully someone else here knows better than I do?

[Extemporaneous]

Originally Posted by David M

Extemp,
I'm sorry, I don't understand the question. Could you describe in more detail what you want to do?

I'm not familiar with Victron so I don't have any opinion of them. Different types of inverters that change between 50 and 60 Hertz are beyond the scope of what I know. Hopefully someone else here knows better than I do?

No David, no reason to be sorry, I wasn't asking a question. I was just pointing out a recent question that Victron answered for me regarding the combining of AC power, the topic you had ended your post with. That's all. I suppose I did just confuse things.
Excuse me.

Extemp.

[Glenn C]

Originally Posted by Extemporaneous

No David, no reason to be sorry, I wasn't asking a question. I was just pointing out a recent question that Victron answered for me regarding the combining of AC power, the topic you had ended your post with. That's all. I suppose I did just confuse things.
Excuse me.

Extemp.

Hi, the Victron probably follows the input frequency, because transformers change volyage, not frequency. glenn