School Bus Conversion Resources

School Bus Conversion Resources (http://www.skoolie.net/forums/)
-   Electrical, Charging and Solar (http://www.skoolie.net/forums/f49/)
-   -   Do I really need a automatic transfer switch? (http://www.skoolie.net/forums/f49/do-i-really-need-a-automatic-transfer-switch-24537.html)

MambaJack 10-10-2018 02:39 PM

Do I really need a automatic transfer switch?
 
Wiring house system. Had originally intended to buy Aims Inverter / Charger, but it hasn't gotten great press in some of the solar forums I have been browsing. Now thinking about splitting charger and inverter.
Is there an issue with wiring it this way?

shore
to small panel
to charger
to batteries
to inverter
to main panel.

Is there a problem with wiring it this way?

john61ct 10-10-2018 02:51 PM

First panel is AC, last is DC, right?

Since I am so rarely on shore power, the only thing that plugs into that is my charger, all AC loads are off inverters. Easy to "switch" to genset.

Aircon can get its own separate shore / gennie connection.

All "transferring" is just plugs and switches, manually.

But that's me.

MambaJack 10-10-2018 02:57 PM

the main panel i have listed is AC, use to power the 110 outlets throughout, refrigerator, laptop, monitor/tv

there would also be a dc panel that i didn't include, coming from the batteries (24v) system, a converter back to 12v, and a 12v fuse panel

family wagon 10-10-2018 03:40 PM

If the main panel is supplied only from the inverter, then your use of AC through that panel is limited by these three things, in order: the inverter's capacity, the charge remaining in the batteries, and the charger's capacity.

It depends on your use case, but sometimes people want to plug their AC panel directly to the shore power. This requires some kind of transfer. Automatic transfer is one way; manual plug-and-socket as suggested by john61ct is another. Wire your main ac panel with a plug as its input; the plug can then be connected to the inverter output or directly to shore power.

If you don't need the convenience of an automatic transfer switch, or if low cost and simplicity are important, then the plug-and-socket approach is a great option.

ol trunt 10-10-2018 04:14 PM

I went with the plug and socket for simplicity. It has only proven how simple I am. As a result of not plugging in where I should have I have managed to try to use inverter power to operate the battery charger that charges the batteries that feed the inverter.:banghead:

An automatic switching device would have eliminated the chance for that mistake.
Jack:popcorn:

john61ct 10-10-2018 04:34 PM

Quote:

Originally Posted by MambaJack (Post 294028)
the main panel i have listed is AC, use to power the 110 outlets throughout, refrigerator, laptop, monitor/tv

If you will be off grid a lot, every one of those items should IMO be run off DC directly, with a focus on efficiency, lowering AH per 24 hour consumption amap.

Inverters waste a lot of power, sometimes over half, and load devices designed for 110AC are rarely as efficient as the DC versions.

sportyrick 10-10-2018 05:43 PM

I use a twist lock plug and sockets, your sockets are your different powers, shore, inverter, generator and your plug goes to your power panel, just plug into which ever power you have at the time and wallah 110V power, no burned up generators, backfeeds or mistakes, a 10 year old could do it. I also have a volt meter letting me know the quality of the 110V power.

PNW_Steve 10-10-2018 08:06 PM

Automatic transfer switch is not necessary but they are handy. The 30amp units are not very expensive.

I had two transfer switches in my last bus. One for shore/generator and one for the inverter.

I ran shore/genny into the main panel and ran branch circuits for everything that was intended to run only when on shore/genny power.

I also ran a single branch circuit that went to the inverter ATS. The inverter fed a sub panel which in turn fed all of the inverter loads.

Dead pirate 10-12-2018 09:42 AM

3 Attachment(s)
This has been a problem for me too. 2 160 solar panels. 6 trojan lead acid. And a 200 watt invertor right of of that. I got a bcdc1240d from redarc to charge and maintain the solar bank while I'm roiling down the highway. Turns out my panels had to be 12 volt. They put out 35 volts. So that's useless. So i just use a dimension 1800 watt invertor and a napa battery charger. I have a 360 watt alternator. When i idle my international dt466e is a generator. Attachment 26449Attachment 26450Attachment 26451

john61ct 10-12-2018 12:41 PM

Quote:

Originally Posted by Dead pirate (Post 294274)
got a bcdc1240d from redarc to charge and maintain the solar bank while I'm roiling down the highway. Turns out my panels had to be 12 volt. They put out 35 volts. So that's useless.

Just get the right controller.

Victron SmartSolar is super-efficient with high-voltage panels, about $100 per 200W, controll from your cellphone.

Running a mains charger from an inverter powered off DC? Rube Goldberg level of inefficiency there, but hey I suppose plenty of alt power to waste so why not.


All times are GMT -5. The time now is 11:32 AM.

Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2019, vBulletin Solutions, Inc.