Doubts about Installing EV Charger with Two Deye Inverters in Parallel

[gabriel_navarro]

Hi everyone,

The main reason for this post is that I’m planning to install a V2C Trydan EV charger, which communicates with the Deye inverters. I’m unsure whether I should connect it to the "Smart Load" port or directly to the electrical panel.

Here’s my setup: I have two Deye SUN-5K-SG03LP1-EU inverters connected in parallel on the same phase. The grid cables go directly into the "Grid" port, and all the household loads (the electrical panel) are connected through the "Load" port. According to the Deye manual, everything is connected to "Backup Loads" (I also have a bypass in case I need to isolate the inverters). I don’t have any loads on the grid side ("Home Loads" in the manual), so I haven’t used a CT. I assumed the inverter would manage fine knowing what it’s injecting and pulling from the grid. The system is set to "Zero Export to Load" mode, allowing me to sell power to the grid and draw from it without any issues.

Now, regarding the charger: I’ve read that the AC ports (GRID, LOAD, and GEN) on parallel inverters might have certain limitations in terms of configuration and synchronization. Specifically, I’m not sure if the "Gen Ports" of both inverters can work together when connected to the same charger or if they operate independently. This brings me to my main questions:

• Can I safely connect the EV charger to the "Gen Port" of both inverters at the same time, or would that cause synchronization issues?
• If it’s possible to connect to both, are there specific configurations I should follow to ensure proper functionality?
• If it’s not advisable to connect to both, would it be better to connect the charger to just one inverter? What should I consider for that setup?

Additionally, I’ve seen some people mention the need for a CT in similar setups. I haven’t used a CT because I assumed the inverter would handle everything without it, given that the grid and loads are on independent lines. Could someone explain why a CT might be necessary in my case? Due to the distance, the CT would be quite far from the inverters, so would I need a meter instead? If so, which one would be recommended?

Lastly, I have 6 Dyness B3 batteries, and I’m concerned that if I connect the charger directly to the electrical panel (instead of the "Smart Load"), it might draw power from the batteries when there’s no solar surplus. I’ve seen that some people with the same charger mention that it communicates with Deye inverters to determine when to draw power and when not to, and others have chargers with current clamps that can detect if there are solar surpluses. However, my concern is that if I want to charge the car at night using grid power, the inverter might pull from the batteries instead, since, unless I connect it to the "Smart Load" port, it would treat the EV charger as just another household load and supply it with battery power like the rest of the house.

Has anyone experienced this or can recommend the best way to connect the charger to avoid this issue?

Thanks in advance for your help!

 

[timselectric]

Can I safely connect the EV charger to the "Gen Port" of both inverters at the same time, or would that cause synchronization issues?

Yes
When operating in parallel, they function as a single unit.

Additionally, I’ve seen some people mention the need for a CT in similar setups

You don't need to use the separate CT's ,if you don't need remote measuring. (Export to CT)

Lastly, I have 6 Dyness B3 batteries, and I’m concerned that if I connect the charger directly to the electrical panel (instead of the "Smart Load"), it might draw power from the batteries when there’s no solar surplus. I’ve seen that some people with the same charger mention that it communicates with Deye inverters to determine when to draw power and when not to, and others have chargers with current clamps that can detect if there are solar surpluses. However, my concern is that if I want to charge the car at night using grid power, the inverter might pull from the batteries instead, since, unless I connect it to the "Smart Load" port, it would treat the EV charger as just another household load and supply it with battery power like the rest of the house.

I'm not familiar with that charger, or how it communicates.
But using the smart load function, gives you total control of when it can charge.

 

[gabriel_navarro]

Yes
When operating in parallel, they function as a single unit.

You don't need to use the separate CT's ,if you don't need remote measuring. (Export to CT)


I'm not familiar with that charger, or how it communicates.
But using the smart load function, gives you total control of when it can charge.

Hi, thanks a lot for your response!

Just to clarify, regarding the CTs, I currently don’t have any installed at all. You mentioned “separate CTs,” but does this mean I don’t need any at all for my setup? I assumed since my grid and loads are on separate lines, the inverter knows what it’s injecting and drawing. Can you confirm if I’m good without them?

About the parallel setup, I came across a discussion in another forum that left me a bit concerned: https://diysolarforum.com/threads/c...in-parallel-mix-gen-port-configuration.68606/ . Deye support mentioned that even in parallel, the GEN ports could work independently. Could you explain a bit more about how that works in a parallel configuration? Do I need to be cautious about this with my setup?

And finally, regarding the EV charger, you’re saying that if I connect the charger to the "Smart Load" port and mark the option for grid use, the Deye inverter will handle the charging without any issues when I plug it in, right? I just want to make sure I won’t have any problems with that setup.

Thanks again for your help!

 

[timselectric]

Just to clarify, regarding the CTs, I currently don’t have any installed at all. You mentioned “separate CTs,” but does this mean I don’t need any at all for my setup? I assumed since my grid and loads are on separate lines, the inverter knows what it’s injecting and drawing. Can you confirm if I’m good without them?

Correct
The internal CT's already see everything that needs to be measured.

Deye support mentioned that even in parallel, the GEN ports could work independently. Could you explain a bit more about how that works in a parallel configuration? Do I need to be cautious about this with my setup?

I'm not aware of that option. It's always been my understanding that they operate in unison, when in parallel configuration. This is typical for all brands.

And finally, regarding the EV charger, you’re saying that if I connect the charger to the "Smart Load" port and mark the option for grid use, the Deye inverter will handle the charging without any issues when I plug it in,

It will control when the charger receives power.
Not sure if your particular charger automatically starts after a power loss or not. But most do.