Off grid type setup that is on grid?

[Mike90250]

The end user or the dealer/installer does the configuration on site, depending on who reads the manual and learns how to program the unit,

[jflorey2]

Can the manufacturer preset the setting to stop power being diverted to the grid , or would I have to do this myself?

You do it yourself. If grid tie is disabled, then the inverter will never sell back to the grid.

[gendil]

THIS subject is similiar to what i had in my mind so i will try and ask the question here rather than opening new thread.......so simple question

wanted to design system that primarly used utility electricity ...if it gone down ...it switchs to solar system ....the load on the solar is trivial ...i wanted it for my friend who had

company of "2-way" super speed internet service and he had couple of "small watt" hubs and switchs that he wont them stay always working


he even suggest that i should design the system that solely depends on the solar but i suggest that he should "off load" his batteries from time to time

when there is electricity form the utilities that will help his batteries and extend their life

what to do ? automatic transfer switch? is it so fast to keep the switces"the load" on? where i can find "low ampergae" ones?any other solution?

[Mike90250]

For computer gear, you want a dual conversion UPS box. It is always ON, it's inverter runs off the batteries, and the batteries are always being charged. No transfer switch, if the grid fails, you don't even miss 1 cycle, Brownout - you are already on batteries, nothing happens.

You select a unit that provides the power and duration your gear requires, and then you add some solar charging to it, if you want to spend the $$ to add solar.

http://www.apc.com/us/en/support/resources-tools/product-selectors.jsp

[gendil]

YES but we do have great amount of black out ...the customer wants solar a system that charges his batteires....problem with ups

is that it is also charges the batteries ....you know now we have 2 circuits trying to charge one battery and BANG ...i need system that uses the ac utility

but when that fails it is safely changes to an always on inverter that is backed up by big battery and solar panel(i completely design my solar system only needs suggestion on the

switching method between the inverter and utility power "

one thought i have is to use chinese inverter that have build in ats when the utility is on the output will be from the utility ac when the utility is off the output will from the inverter

however at that point i must open up the inverter and disable the charger circuit that is bulid in this inverter this will allow my mppt controller to take care of batteries charging process

the gain of this process is that when the ac utility is on the output will be taken from ac utlity and the inverter will now be totally 100% shutdown


this is far more better than using normal inverter and ats externally .you know it is not logical to leave an invetrer on all the time ...however the disadvantage of this method (chinse

inverter witth build in ats) is that now i have to open up the new inevter and "modify" it by disabling the charger circuit ...some thing i really dont like doing



or may be you offer me 3TH solution?

[SunEagle]

YES but we do have great amount of black out ...the customer wants solar a system that charges his batteires....problem with ups

is that it is also charges the batteries ....you know now we have 2 circuits trying to charge one battery and BANG ...i need system that uses the ac utility

but when that fails it is safely changes to an always on inverter that is backed up by big battery and solar panel(i completely design my solar system only needs suggestion on the

switching method between the inverter and utility power "

one thought i have is to use chinese inverter that have build in ats when the utility is on the output will be from the utility ac when the utility is off the output will from the inverter

however at that point i must open up the inverter and disable the charger circuit that is bulid in this inverter this will allow my mppt controller to take care of batteries charging process

the gain of this process is that when the ac utility is on the output will be taken from ac utlity and the inverter will now be totally 100% shutdown


this is far more better than using normal inverter and ats externally .you know it is not logical to leave an invetrer on all the time ...however the disadvantage of this method (chinse

inverter witth build in ats) is that now i have to open up the new inevter and "modify" it by disabling the charger circuit ...some thing i really dont like doing



or may be you offer me 3TH solution?

You might still look into a UPS that doesn't care where it gets it power from. Even if there is a delay switching from the grid to the solar battery system the UPS will continue to power the critical loads.

That way you put in a standard transfer switch that will use the grid to power the UPS and then it would transfer to the solar/battery system when the grid goes down. Even if there is a "break before make" operation which will stop power going to the UPS for a short time internal, but the UPS battery will keep the load happy and running.

[gendil]

That way you put in a standard transfer switch that will use the grid to power the UPS and then it would transfer to the solar/battery system when the grid goes down. "break .

ups will be my source of ac when the utility is on ...when utility is off switch will go to ??? solar battery system will also have an inverter

that way i have to buy ups + inverter....too much cost

[Sunking]

company of "2-way" super speed internet service and he had couple of "small watt" hubs and switchs that he wont them stay always working

I have been doing this for 40 years professionally. You do not need solar to do any of that, not would any biz or professional would do that. If in fact you are talking small power requirement just size the battery to however many days you want. Far less expensive and way more reliable.

[SunEagle]

ups will be my source of ac when the utility is on ...when utility is off switch will go to ??? solar battery system will also have an inverter

that way i have to buy ups + inverter....too much cost

I am sorry but cost will always be a big factor when you want to build a solar/battery system.

As for a instant transfer switch that is not a fake type made in China I would imagine the cost of that will be much more than a couple of small UPS systems sized for the couple of minutes you would wait for a standard transfer switch to work between choosing grid power or battery power.

I really can't help you if you don't understand you will be paying for this equipment one way or the other but neither will be low cost.