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Thread: Changeover/bypass switches for hybrid inverters

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    Changeover/bypass switches for hybrid inverters

    Changeover/ bypass switch for a hybrid inverter. Good idea and where would you install it, considering the hybrid input is both an input and output. You would have to install the switch on the inverter output?

    Throw in a string of solar panels (PV) as some like to call them.

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    I use a changeover to bypass the whole inverter for service and maintenance etc.

    Sent from my CPH2197 using Tapatalk

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    I have only ever done 3 invertor installations where the invertor is only used in the event of loadshedding, so I treated the output of the invertor like a generator through the changeover switch.

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    On my small 1kw systems I have an auto change over of the inverter output so that when the grid is on that the sockets are not limited to 1 kW. I also have a Change over in input of inveter for maintenance etc.

    On my bigger hybrids I have no changeover on output as I want it to be on inverter and solar etc.

    I do have a changeover again on input of the hybrid for maintenance etc of inverter and fan remove it.

    Sent from my CPH2197 using Tapatalk

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    Quote Originally Posted by Dylboy View Post
    I use a changeover to bypass the whole inverter for service and maintenance etc.

    Sent from my CPH2197 using Tapatalk
    Have you ever installed and connected a Hybrid inverter?

    Post a sketch so we can see how you separate/isolate the inverter input, when in bypass.

    I have been going through many sketches and they all seem to have the power to the mains side of the changeover switch and the inverter input connected together, which effectively would still provide power to the "input" inverter when the system is in bypass.

    The only way to isolate the inverter when in bypass, would be to do what I do is fit a double pole combo mcb next to the changeover switch, which must be switch off when the switch is in bypass otherwise there is still power to the inverter input.

    To complicate it even more, throw in a hybrid inverter which is connected to solar panels. Its becomes a complex switching operation, which could explain why this such and important topic.

    Just to complicate things even more, add in a neutral/earth bond relay

    I believe it should be law to have a laminated isolation sheet installed on or next to the inverter as well as all the correct labels. It doent help just having labels.

    I went to a site a couple week ago and I battled to figue out how to make the installation safe enough to work on it, and I have been doing a ton of research, installed plenty of standby inverters and work in the electrical industry.

    A brief description would make life a lot easier. Some might say you can just phone the installer, when those start boiling and and gas starts spraying all over the place, it is better to have an understanding of how the system works, not everyone is a DIY solar expert.

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    Quote Originally Posted by Dylboy View Post
    On my small 1kw systems I have an auto change over of the inverter output so that when the grid is on that the sockets are not limited to 1 kW. I also have a Change over in input of inveter for maintenance etc.

    On my bigger hybrids I have no changeover on output as I want it to be on inverter and solar etc.

    I do have a changeover again on input of the hybrid for maintenance etc of inverter and fan remove it.

    Sent from my CPH2197 using Tapatalk
    On the small units I have a plug top on the input and a socket outlet on the output, if there is a problem, you pull the plug out the wall socket , you pull the plug top( essential circuit) out the inverter socket and plug the essential circuit into the wall socket (mains). the inverter can be removed and serviced. All the essential sockets mounted as required, are all blue and labeled inverter.

    I have found that these small Meccer units dont last longer than a year and the batteries are done. The reason they dont last could be a result of a number of things. Loaf shedding stops and the units are left unplugged which results in the battery draining beyond 10.5 VDC. Other reasons could be that the person has added too much load or used the wrong type of battery etc.

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    Quote Originally Posted by Isetech View Post
    Have you ever installed and connected a Hybrid inverter?

    Post a sketch so we can see how you separate/isolate the inverter input, when in bypass.

    I have been going through many sketches and they all seem to have the power to the mains side of the changeover switch and the inverter input connected together, which effectively would still provide power to the "input" inverter when the system is in bypass.

    The only way to isolate the inverter when in bypass, would be to do what I do is fit a double pole combo mcb next to the changeover switch, which must be switch off when the switch is in bypass otherwise there is still power to the inverter input.

    To complicate it even more, throw in a hybrid inverter which is connected to solar panels. Its becomes a complex switching operation, which could explain why this such and important topic.

    Just to complicate things even more, add in a neutral/earth bond relay

    I believe it should be law to have a laminated isolation sheet installed on or next to the inverter as well as all the correct labels. It doent help just having labels.

    I went to a site a couple week ago and I battled to figue out how to make the installation safe enough to work on it, and I have been doing a ton of research, installed plenty of standby inverters and work in the electrical industry.

    A brief description would make life a lot easier. Some might say you can just phone the installer, when those start boiling and and gas starts spraying all over the place, it is better to have an understanding of how the system works, not everyone is a DIY solar expert.
    Ah yes to have that isolated I have a DP isolator on the feed to inverter as well.

    I also type out a switching procedure and label everything. Also if they really need to isolate the deed cable go to the CB feeding the inverter haha.
    I too have tried many sketches for the isolator in bypass thing and best solution is the DP isolator. I sometimes also use a double like MCB for the same thing and further protection mostly for short circuit.

    Sent from my CPH2197 using Tapatalk

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