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Will check if I can get it sorted. Installed a change over switch to put my non essentials back to eskom for the time being until I can get answers.

from my experience it does not restart with the micro inverter. 

Yes it does but I'm ok with the BMS managing the individual batteries in the bank.  With CAN, the BMS now also limits charge and discharge rates based on SOC instead of the inverter controlling c

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On 2020/08/20 at 12:51 PM, Halcyon said:

Hi Johan, do a voltage check between load neutral and earth when AC grid is off.  One of the Sunsynk manuals specifically states you will read 110v with a floating neutral unless resolved with a relay.  My load output neutral earth measured +- 50V when in island mode but this was resolved when I installed a relay.  The 50V gave me a little bite when touched. Surprisingly my E/L did trip when you press the test button without relay installed but I was told that is not a reliable test for safe functioning.  The Sunsynk definitely does not have an internal relay doing the bonding job like a Victron.  I bought a R100 40A NO relay from ACDC.  It is so small I fixed it with cable ties inside the inverter.  As you know there is a lot of space inside once you open the front cover.

@HalcyonDo you perhaps have the product code for that relay? Voltex this side is useless and would like to order a couple to use with my future installations.

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On 2020/09/27 at 9:04 AM, Johann1982 said:

@HalcyonDo you perhaps have the product code for that relay? Voltex this side is useless and would like to order a couple to use with my future installations.

Hi Johann, Yes the one I have is the same as Justin's as per the link he posted.  Just marked as 12V somewhere in error on the page but must be the 230V 40A version.

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On 2020/09/27 at 11:07 AM, Bloubul7 said:

I used a 60a solid state relay from Communica.  Might be a little overkill but should last

https://www.communica.co.za/products/ksi600a60-l

20200927_110424.thumb.jpg.33b0d158d2bc0865d81298f766a1d740.jpg

"Solid state relays" do not provide electrical isolation.  When the MOSFETs on the solid state relay fails, it'll fail short circuit.  Mechanical relays don't have this problem.  You really should not be using that relay.

EDIT: Also it looks like your are connecting the relay using a low voltage circuit?  If that is the case, you've effectively removed the isolation from the low voltage circuit.  A very big no-no.  Anything connected to that low voltage circuit (including network cables) can become live.

Edited by Gnome
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12 minutes ago, Gnome said:

"Solid state relays" do not provide electrical isolation.  When the MOSFETs on the solid state relay fails, it'll fail short circuit.  Mechanical relays don't have this problem.  You really should not be using that relay.

EDIT: Also it looks like your are connecting the relay using a low voltage circuit?  If that is the case, you've effectively removed the isolation from the low voltage circuit.  A very big no-no.  Anything connected to that low voltage circuit (including network cables) can become live.

Thanks,

Will replaced it with a mechanical relay.  It is driven by 220V, the inverter provides a 5 amp 220v islanding switch

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3 minutes ago, Bloubul7 said:

Thanks,

Will replaced it with a mechanical relay.  It is driven by 220V, the inverter provides a 5 amp 220v islanding switch

Actually I stand to be corrected:  They internally do use opto-isolator to create isolation: https://www.electronics-tutorials.ws/power/solid-state-relay.html

Just verify in the specification of the relay you bought that it does actually isolate.

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2 hours ago, Gnome said:

"Solid state relays" do not provide electrical isolation.  When the MOSFETs on the solid state relay fails, it'll fail short circuit.  Mechanical relays don't have this problem.  You really should not be using that relay.

I think you may be confusing failure modes... Solid state relays are all isolated, and pretty much only a lightning strike could break down the control to load isolation.

The main safety drawback of SSRs is that the primary failure mode is fail-closed - i.e. if the output fails, it fails in such a way that it carries on conducting.  Mechanical relays can fail closed, but it is extremely rare (something like 1:10^7 for typical relays) - if they fail, they usually fail open - i.e. load disconnected, which is generally a much safer failure mode.

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14 hours ago, JustinSchoeman said:

I think you may be confusing failure modes... Solid state relays are all isolated

To be honest with you, I figured from first principles.  Only after did I go read more about it.  I knew that solid state relays were just MOSFETs.  And MOSFETs always fail short-circuit.  However the opto-isolators is pretty decent isolation.  The reason I thought this is because you don't typically expect a relay to consume current on the switching side, only the coil side.  Bit of a drawback with using them I guess.

14 hours ago, JustinSchoeman said:

only a lightning strike could break down the control to load isolation.

Most opto-isolators are rated roughly 4kV, so it doesn't take *that* much to break the barrier (lightning tests typically start at 200kV up to 1MV).  In terms of break-down voltage it is much easier to get higher kV ratings using opto-isolators than relays anyway.  Isolation is more about failure mode than breakdown voltage.

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  • 2 weeks later...

Anyone with more than 8kwp of panels and the sunsynk 8kw inverter? 

Yesterday I had my first 50kwh of pv production and the display on the inverter seems to only record 50kwh and stops counting pv production beyond this. 

Today looks like another 51kwh solar day and the inverter stopped recording pv production. 

Edited by Achmat
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36 minutes ago, Werner67 said:

Hi Achmat

I do record more that 50kw a few times when able to use all the power.

have 8.6kw of panels.

Sunsynk support updated my device on Friday so now the inverter shows the full pv production. 

Seconds pic was before the update. 

Screenshot_20201016-183953_Gallery.jpg

Screenshot_20201018-203810_Photos.jpg

Edited by Achmat
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  • 3 weeks later...

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