Draft of electric layout
- Thread starter mbsprinter144
- Start date
DiploStrat
Expedition Leader
Two Comments
Don't make this harder than it has to be:
-- First, determine the voltage of your vehicle's charging system; if it matches that of your batteries, simply use an intelligent relay, e.g. Bluesea ACR. This will assure that a charge at either battery will be shared with the other and allow self jump. (Of course, build your system correctly [see my website] and neither of your batteries will ever go dead.)
-- Second, use an inverter/charger, e.g. Magnum (http://www.magnum-dimensions.com/mo...er-chargers?field_input_current_tid_selective[]=89&field_output_waveform_value_selective[]=1&field_output_power_watts_value[min]=200&field_output_power_watts_value[max]=15000&field_output_frequency_value_selective[]=2&field_output_voltage_value_selective[]=1&field_frequency_value_selective[]=2&field_phase_value_selective[]=1), and you get an internal automatic transfer switch. All of your wiring just got a lot easier.
This has been done before, don't try to reinvent the wheel.
N.B. All of the above applies to FLA or AGM batteries. LiFePO4 similar, but with significant differences.
Don't make this harder than it has to be:
-- First, determine the voltage of your vehicle's charging system; if it matches that of your batteries, simply use an intelligent relay, e.g. Bluesea ACR. This will assure that a charge at either battery will be shared with the other and allow self jump. (Of course, build your system correctly [see my website] and neither of your batteries will ever go dead.)
-- Second, use an inverter/charger, e.g. Magnum (http://www.magnum-dimensions.com/mo...er-chargers?field_input_current_tid_selective[]=89&field_output_waveform_value_selective[]=1&field_output_power_watts_value[min]=200&field_output_power_watts_value[max]=15000&field_output_frequency_value_selective[]=2&field_output_voltage_value_selective[]=1&field_frequency_value_selective[]=2&field_phase_value_selective[]=1), and you get an internal automatic transfer switch. All of your wiring just got a lot easier.
This has been done before, don't try to reinvent the wheel.
N.B. All of the above applies to FLA or AGM batteries. LiFePO4 similar, but with significant differences.
DiploStrat
Expedition Leader
dwh
Tail-End Charlie
Bloody hell. I was editing my post to say just that since I hit post too soon and left that part out. And while editing, the post magically disappeared.
But at least you preserved it with a quote.
All is not lost.But yea, if you just plug the shore power into the generator, you only need the one transfer switch.
The second transfer switch is for a built-in RV gen.
DiploStrat
Expedition Leader
Even easier, no user supplied transfer switch needed at all. Basically, you run a male 110v cord from the inverter/charger. Make it long enough to plug into shore power or coil it up and plug it into your generator. It is really that simple.
dwh
Tail-End Charlie
One step at a time. First let the OP figure out how all this electrocrap works together, then simplify. Until today he didn't even know about transfer switches.
DiploStrat
Expedition Leader
Hence my suggestion that he build a system that doesn't need one!
Again, KISS
Again, KISS
mbsprinter144
Observer
Ok so I plug in either the shore power line or the generator, easy. I remember reading somewhere that the Magnum will pull from battery power and generator power to run things like AC that may require more than either can handle alone. Is this correct?
Version 5 attached
Version 5 attached
dwh
Tail-End Charlie
Not exactly correct.
Some models of inverter/chargers have that feature. I know Xantrex has at least one that can do that. It is mainly for handling large momentary loads. For instance if you have a 2000w generator but your air conditioning pulls more than 2000w when the compressor kicks on.
But the unit still has to be rated high enough to handle the full load. So if you had a 2000w gen, but the a/c startup was say 2600w, you would need an inverter/charger with at least a 2600w "momentary surge" rating.
Edit: Which means the unit could handle the entire load from battery if there was nothing coming in on shore power. The battery might not be able to supply the load for very long though...depending on how big the battery (or bank) is.
And the unit has to first be both an inverter and charger with a shore power cord and an internal transfer switch to even be able to add that feature. A standalone inverter doesn't have either.
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dwh
Tail-End Charlie
Also, when the unit is being forced to draw from the battery to supplement the the incoming power from shore/gen, then it does not have any incoming power left over to charge the battery.
Not that it would anyway - it will either feed power to the battery, or draw power from the battery, but not both at the same time.
Not that it would anyway - it will either feed power to the battery, or draw power from the battery, but not both at the same time.
mbsprinter144
Observer
Got it. Yeah, I am thinking the small Honda 2000 gen may have some trouble staring the AC so would be good to have batteries to help that if I do not have shore power.
DiploStrat
Expedition Leader
In, re. Starting an A/C with an inverter.
Most air conditioners need about five times their running load to start. So, if your air conditioner draws 500w when the compressor is running, you will probably need an inverter of at least 2500w to start it.
Will a 2000w genset start it? Depends. Most conventional generators can take a surge by simply allowing the prime mover to slow down for a few revs. Will an inverter/generator like the Honda or Yamaha do this? I have no idea.
An inverter cannot sag like this, so it must be sized to handle the entire load. To reinforce dwh's point, a Magnum inverter/charger, with the hybrid power feature may be able to protect an undersized generator, but the inverter/charger MUST be sized large enough to cover the starting surge.
In my case, a 2800w Magnum would start a 6k BTU air conditioner. Never tried it with a generator.
Most air conditioners need about five times their running load to start. So, if your air conditioner draws 500w when the compressor is running, you will probably need an inverter of at least 2500w to start it.
Will a 2000w genset start it? Depends. Most conventional generators can take a surge by simply allowing the prime mover to slow down for a few revs. Will an inverter/generator like the Honda or Yamaha do this? I have no idea.
An inverter cannot sag like this, so it must be sized to handle the entire load. To reinforce dwh's point, a Magnum inverter/charger, with the hybrid power feature may be able to protect an undersized generator, but the inverter/charger MUST be sized large enough to cover the starting surge.
In my case, a 2800w Magnum would start a 6k BTU air conditioner. Never tried it with a generator.