Generator Integration

Installation guidelines 

When installing a generator, it is best to ensure the generator is twice the inverter size, this is so the generator can supply loads and charge batteries. 

It is also best to run the generator through the GEN port. Make sure the generator is grounded with the inverter ground and that the generator has an NE-bond. 

However, when you're generator is equipped with a build in earth leakage/RCD you will have to connect the Generator on the GRID port and make use of an automated NE-bonding contactor on the LOAD port. If you have a permanent NE-bond on the Load side, it will always trip your generator's earth leakage/RCD whether it is on the GRID port or GEN port. You can only use the GRID port because it is the only port that make the "Signal Island mode" signal, function as required to make and break the NE-bond contactor for you LOAD port when needed.

In a parallel system you must connect the generator supply to all the inverters. Some older manuals still state this is not possible, but you must ensure that your inverters run on the later firmware versions.

For 3 phase inverters you need a 3-phase generator, you cannot supply a 3-phasehase inverter with a single phase generator.

You can connect one phase of a 3-phase generator to supply a single-phase inverter but take note that one phase power capability is 1/3 of the generators power specification.  So, if when you have a 15KVA generator a single phase is capable of 5KVA.

The port on the inverters gets labeled as "GEN" but can be used for 2 other functionalities, but not simultaneously. Ensure that you only use it for one function, in this case "Generator"

Please ensure that the AC power from the generator operates at 50Hz. If the AC power measures above 51.5Hz the inverters will not accept the generators power.   This default setting of 51.5Hz can be adjusted under the inverter's grid settings, but it is best to ensure that you generator power does operates between 49Hz and 51Hz.

The Grid Voltage and Frequency window of operation is both applicable to the Grid power and the Generator power.  You need to adjust this frequency under Grid Settings - Connect and Grid Settings - IP.

When connecting the generator to the GRID port please ensure the CT is positioned to pick up live wire of the generator to avoid export to the generator. 

The latest firmware does give a Gen on grid option on the Sunsynk Connect platform. This will make the "generator signal " stay close when AC power is detected on the "grid port". 

The generator settings are configured under the AUX setting, you will select Gen Input first.

Smaller generators can be used but then you will need to ensure that the Gen Peak shaving settings is enabled. 

This will then automatically enable your use timer (System mode 1) because the inverter will have to supply power from the batteries, should the max power from the generator be exceeded in the power demanded.  

When you select Gen peak shaving, please insert the max power of your generator in the box where the value is underlined red. 

The GEN Load OFF Bat cannot be adjusted but it indicates the SOC point. When the battery SOC/Voltage gets higher than this set point the Gen Signal will be turned off.

The GEN Load ON Batt can be set to the value of SOC/Voltage of the battery at which you need the "GEN signal" to call in generator (this GEN signal will have to be wired to you're generator's auto start controller and signal the remote start option). Manual generators will also only be accepted once the battery is below this set percentage. On the "Sunsynk Connect" App or web page the "GEN Load ON Batt" setting is under battery settings as "Gen Start(10-90%), please see images below. 

The terminals for "GEN signal" on the inverter are labeled G-S or G-start depending on the model. This is a dry contact that will close when the battery SOC/Voltage fall below the "Gen Load on Batt" setting. 

Ensure under battery settings that "GEN charge" has been selected and "GEN signal" has been enabled.

Note that the terminals can be at different pin positions depending on the inverter models, but they will be labeled. Please consult you specific model's latest user manual. 

We have found that when the "Signal Island Mode" is set and you use Software version COMM E.4.3.9 that the "Gen signal" operates on the G-valve position on the 8kw(std) and MAX(16KW) inverters. Also check for this on the 12KW-1P (single phase) machines.  On the 12KW-3P (three phase) machines the "gen signal" does operate on the G-start pins.

G-start pins on the 8kw(std) Max(16kw) and 12kw single phase inverters.

G-start pins on the 8kw, 10k2 and 12KW 3-phase inverters

G-start pins on 50kw inverter

The inverters do not accept both grid and gen power simultaneously, because the AC power will not be synchronized. When grid is on the signal will not be enabled so the generator cannot be pulled in. We have noted that the firmware can affect the GS signal starting at set battery percentage, please double check with the firmware engineers if the firmware used is the latest.

When the "USE timer" is enabled, please ensure that you have "Gen box" selected so that the GEN signal will function.  The "GEN Load ON Bat" is still the setting where the GEN signal will close, but now the set target SOC value, in the time slot will override the "GEN LOAD OFF Bat" value to stop the "GEN signal".  This way you can turn the generator off when you battery has reached a specific lever of charge SOC/Voltage. 

The End.

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