Hi

Summary 

During the course of a 50kw Deye install, it came to light that this inverter automatically creates a neutral bond internally (no external relay or contactor at all) when in off grid mode.

This is similar to other manufacturers such as the Solis, which do the bond internally. 

As clarified below, this function is specific to the 3 phase Sunsynk / Deye inverters. All of them do the neutral earth bond internally. For this to function, signal island mode has to be enabled. 

This has been confirmed by the manufacturers themselves as well as by testing with a plug tester, with signal island mode off/on. 

 

Full details below :

Initial queries 

Initial queries regarding this brought out a lot of confusion, with many installers outright negating the idea of the inverter doing the bond internally. 

Based on the single phase machines not having it internally, which in itself is a issue many installers don't even know nor worry about, the fact that some of these inverters do have it built-in was even more of a rarity. Master installers with many such installs under their belts were unaware of this. 

The technical experts at Segen solar themselves were not sure, similar was the case on the Deye whatsapp group. I thus contacted the manufacturers directly to verify this. 

 

Relay vs Permanent Bond 

This is not the topic at hand, we are simply discussing here whether the inverter does the bond internally or not. 

 

Manual

This doesn't appear in any of the manuals of either manufacturer as far as I know. A great injustice indeed.

In fact, the Sunsynk manual specifies that the bond has to be created externally. Segen solar themselves sell a specific neutral earth bond relay for the 50kw machine, which one would make no sense to purchase if the machine does the same thing internally. 

 

Manufacturer Support Desk

The first line of support at Sunsynk and Deye as well were not clued up on the issue. 

Sunsynk support help desk had to place me on hold, and after a few minutes consulting with the engineers told me that ALL their 3 phase inverters have the built in automatic neutral earth bond. 

However, signal island mode has to be ticked for it to function. 

CNBM had to get their technical support team to contact me, after which he had to contact Deye engineers directly in China, who confirmed the same. See the quotation below. 

[04/17, 4:55 pm)] Only the 3 phase have built-in earth bond

[04/17, 4:55 pm] In South Africa only 12/20/50K available in 3 phase

[04/17, 4:55 pm] 12K/20/50K are 3 phase

 

Testing and confirmation 

This built in neutral earth bond has been tested with a plug tester, 

- When signal island mode is ticked, all 3 lights come on and the earth leakage trips. 

- With signal island mode unticked, the earth light stays off. 

With my limited electrical knowledge I contacted a few master electricians who confirmed that the machine is in fact doing the bond internally. 

 

Signal Island Mode 

There is now a difference in the functionality of the "signal island mode" setting between the single phase and 3 phase inverters. 

On the signal phase it simply sends out the signal from the specified pins, to the externally installed contactor. 

On the 3 phase inverters, the "signal island mode" is not just the signal, it also creates the bond itself within the inverter.

 

Testing

The above tests were carried out on a Deye 50kw inverter, and I am not able to test on the other smaller 3 phase inverters. 

I thus request installers working with 3 phase Sunsynk / Deye machines of any type to carry out this very test and advise of the results on this thread, so we can get some real clarification based on actual testing of the units in SA. 

This definitely is a strange one, bound to cause much confusion in general, with one manufacturer producing certain inverters which do not do the neutral earth bond internally, and others which do so. 

There may very well be some batches of 3 phase inverters which don't do the bond internally, so do your tests thoroughly and do not rely on this information.

I simply thought it's important to share this info with you, given the time and effort it took to get to some conclusion on this matter. 

Edited April 18, 20242 yr by abd7

19 minutes ago, abd7 said:

Hi

During the course of a 50kw Deye install, it came to light that this inverter automatically creates a neutral bond internally (no external relay or contactor at all) when in off grid mode. This is similar to other manufacturers such as the Solis, which do the bond internally. 

As clarified below, this function is specific to the 3 phase Sunsynk / Deye inverters. 

For this to function, signal island mode has to be enabled. 

 

Initial queries 

Initial queries regarding this brought out a lot of confusion, with many installers outright negating the idea of the inverter doing the bond internally. 

Based on the single phase machines not having it internally, which in itself is a issue many installers don't even know nor worry about, the fact that some of these inverters do have it built-in was even more of a rarity. Master installers with many such installs under their belts were unaware of this. 

The technical experts at Segen solar themselves were not sure, similar was the case on the Deye whatsapp group. I thus contacted the manufacturers directly to verify this. 

Relay vs Permanent Bond 

This is not the topic at hand, we are simply discussing here whether the inverter does the bond internally (with a relay obviously) or not. 

 

Manual

This doesn't appear in any of the manuals of either manufacturer as far as I know. A great injustice indeed.

In fact, the Sunsynk manual specifies that the bond has to be created externally. Segen solar themselves sell a specific neutral earth bond relay for the 50kw machine, which one would make no sense to purchase if the machine does the same thing internally. 

 

Manufacturer Support Desk

The first line of support at Sunsynk and Deye as well were not clued up on the issue. 

Sunsynk support help desk had to place me on hold, and after a few minutes consulting with the engineers told me that ALL their 3 phase inverters have the built in automatic neutral earth bond. 

However, signal island mode has to be ticked for it to function. 

CNBM had to get their technical support team to contact me, after which he had to contact Deye engineers directly in China, who confirmed the same. See the quotation below. 

[04/17, 4:55 pm)] Only the 3 phase have built-in earth bond

[04/17, 4:55 pm] In South Africa only 12/20/50K available in 3 phase

[04/17, 4:55 pm] 12K/20/50K are 3 phase

Testing and confirmation 

This built in neutral earth bond has been tested with a plug tester, 

- When signal island mode is ticked, all 3 lights come on and the earth leakage trips. 

- With signal island mode unticked, the earth light stays off. 

With my limited electrical knowledge I contacted a few master electricians who confirmed that the machine is in fact doing the bond internally. 

 

Signal Island Mode 

There is now a difference in the functionality of the "signal island mode" setting between the single phase and 3 phase inverters. 

On the signal phase it simply sends out the signal from the specified pins, to the externally installed contactor. 

On the 3 phase inverters, the "signal island mode" is not just the signal, it also creates the bond itself within the inverter.

 

Testing

The above tests were carried out on a Deye 50kw inverter, and I am not able to test on the other smaller 3 phase inverters. 

I thus request installers working with 3 phase Sunsynk / Deye machines of any type to carry out this very test and advise of the results on this thread, so we can get some real clarification based on actual testing of the units in SA. 

This definitely is a strange one, bound to cause much confusion in general, with one manufacturer producing certain inverters which do not do the neutral earth bond internally, and others which do so. 

There may very well be some batches of 3 phase inverters which don't do the bond internally, so do your tests thoroughly and do not rely on this information.

I simply thought it's important to share this info with you, given the time and effort it took to get to some conclusion on this matter. 

Interesting that the support mention the 12kW is only 3 ph while the 1 ph is now being sold. 

All the jargon aside, let's examine why we go to the trouble of carrying out a Relayed bond & that's to make the machine safe so that the RCD is operational. That's the reason behind it. If the machine is carrying out this function because of I built relays then I'd say you need to do nothing. 

However, I have been installing these machines for quite a while & have commissioned many 12kW versions. There is zero product information advising of this hardware change & that is very disappointing. 

I'm not surprised though, because money is spent in marketing & a whole lot of other bottom line stuff. The editing & updating of a manual is clearly not that important to them. 

I have seen much worse though. The ATESS user manual is far worse....in fact I'm willing to say across the board there is just a massive lack of proper manual & technical writing of these machines.

6 minutes ago, Scorp007 said:

Interesting that the support mention the 12kW is only 3 ph while the 1 ph is now being sold. 

He is not negating that there's a 12kw single phase. 

Just pointing out that the 3 phase machines which he referred to include 12kw,20kw, and 50kw inverters. 

Just now, abd7 said:

He is not negating that there's a 12kw single phase. 

Just pointing out that the 3 phase machines which he referred to include 12kw,20kw, and 50kw inverters. 

Thanks for clarification. 

Just recieved written confirmation from Sunsynk themselves regarding this :

 

I can confirm that the 50kW HV Sunsynk inverters do have a built in earth neutral bond relay.  All of our 3 phase inverters have this.

On 2024/04/17 at 9:51 PM, abd7 said:

Hi

Summary 

During the course of a 50kw Deye install, it came to light that this inverter automatically creates a neutral bond internally (no external relay or contactor at all) when in off grid mode.

This is similar to other manufacturers such as the Solis, which do the bond internally. 

As clarified below, this function is specific to the 3 phase Sunsynk / Deye inverters. All of them do the neutral earth bond internally. For this to function, signal island mode has to be enabled. 

This has been confirmed by the manufacturers themselves as well as by testing with a plug tester, with signal island mode off/on. 

 

Full details below :

Initial queries 

Initial queries regarding this brought out a lot of confusion, with many installers outright negating the idea of the inverter doing the bond internally. 

Based on the single phase machines not having it internally, which in itself is a issue many installers don't even know nor worry about, the fact that some of these inverters do have it built-in was even more of a rarity. Master installers with many such installs under their belts were unaware of this. 

The technical experts at Segen solar themselves were not sure, similar was the case on the Deye whatsapp group. I thus contacted the manufacturers directly to verify this. 

 

Relay vs Permanent Bond 

This is not the topic at hand, we are simply discussing here whether the inverter does the bond internally or not. 

 

Manual

This doesn't appear in any of the manuals of either manufacturer as far as I know. A great injustice indeed.

In fact, the Sunsynk manual specifies that the bond has to be created externally. Segen solar themselves sell a specific neutral earth bond relay for the 50kw machine, which one would make no sense to purchase if the machine does the same thing internally. 

 

Manufacturer Support Desk

The first line of support at Sunsynk and Deye as well were not clued up on the issue. 

Sunsynk support help desk had to place me on hold, and after a few minutes consulting with the engineers told me that ALL their 3 phase inverters have the built in automatic neutral earth bond. 

However, signal island mode has to be ticked for it to function. 

CNBM had to get their technical support team to contact me, after which he had to contact Deye engineers directly in China, who confirmed the same. See the quotation below. 

[04/17, 4:55 pm)] Only the 3 phase have built-in earth bond

[04/17, 4:55 pm] In South Africa only 12/20/50K available in 3 phase

[04/17, 4:55 pm] 12K/20/50K are 3 phase

 

Testing and confirmation 

This built in neutral earth bond has been tested with a plug tester, 

- When signal island mode is ticked, all 3 lights come on and the earth leakage trips. 

- With signal island mode unticked, the earth light stays off. 

With my limited electrical knowledge I contacted a few master electricians who confirmed that the machine is in fact doing the bond internally. 

 

Signal Island Mode 

There is now a difference in the functionality of the "signal island mode" setting between the single phase and 3 phase inverters. 

On the signal phase it simply sends out the signal from the specified pins, to the externally installed contactor. 

On the 3 phase inverters, the "signal island mode" is not just the signal, it also creates the bond itself within the inverter.

 

Testing

The above tests were carried out on a Deye 50kw inverter, and I am not able to test on the other smaller 3 phase inverters. 

I thus request installers working with 3 phase Sunsynk / Deye machines of any type to carry out this very test and advise of the results on this thread, so we can get some real clarification based on actual testing of the units in SA. 

This definitely is a strange one, bound to cause much confusion in general, with one manufacturer producing certain inverters which do not do the neutral earth bond internally, and others which do so. 

There may very well be some batches of 3 phase inverters which don't do the bond internally, so do your tests thoroughly and do not rely on this information.

I simply thought it's important to share this info with you, given the time and effort it took to get to some conclusion on this matter. 

Hi @abd7 thanks for this post , bonding/islanding is one of my pet subjects and your post is one of the most valuable I have encountered thus far . It prompts me to make the following statements :

As we can conclude from your findings and those of others , the manufacturers of inverters may or may not include support for bonding . The Sunsynk provides a helper/convenience function   via the ATS240 programmable output , it may even provide a full bonding support. The Axpert newer models has full support , but the older models have no support.

But the important thing is that it is not up to the product manufacturer to add these functions, the installer and commissioner have the sole responsibility/liability to ensure that bonding is provided , wether via these helper functions or if needed be , or if so required , from first principles.

 

Very important is that @abd7 uses a proper plug tester to verify bonding during islanding. This is very important , as the test button on your ELD does not reveal or prove that your neatral is bonded to earth.

 

And by the way , @TonyH has done us a big favour to point out that permanent bonding of a island is illegal . please consider his post below :

 

 

 

 

 

 

21 minutes ago, BritishRacingGreen said:

Hi @abd7 thanks for this post , bonding/islanding is one of my pet subjects and your post is one of the most valuable I have encountered thus far . It prompts me to make the following statements :

As we can conclude from your findings and those of others , the manufacturers of inverters may or may not include support for bonding . The Sunsynk provides a helper/convenience function   via the ATS240 programmable output , it may even provide a full bonding support. The Axpert newer models has full support , but the older models have no support.

But the important thing is that it is not up to the product manufacturer to add these functions, the installer and commissioner have the sole responsibility/liability to ensure that bonding is provided , wether via these helper functions or if needed be , or if so required , from first principles.

 

Very important is that @abd7 uses a proper plug tester to verify bonding during islanding. This is very important , as the test button on your ELD does not reveal or prove that your neatral is bonded to earth.

 

And by the way , @TonyH has done us a big favour to point out that permanent bonding of a island is illegal . please consider his post below :

 

 

 

 

 

 

I also want to point out that the failure modes of bonding are undetectable , i.e. failing of bonding relay to open or short  circuit goes undetected as a fault. Therefore it is actually important to perform an evaluation test periodically , say every 3 months max. The probability of a bonding being at fault  while the system is islanding is so much higher in South Africa because of planned load shedding and unplanned outages. 

Edited May 6, 20242 yr by BritishRacingGreen