EG4 18Kpv Rapid Shutdown - No clear instructions

[Jdcarrol]

FYI: EG4 just posted a document:

Eg4 18KPv External RSD Initiator Installation Instructions

Here is a PDF guide on how to install a RSD initiator for the Eg4 18KPv.

diysolarforum.com

@FilterGuy , you've helped respond to my questions in the past and I have questions similar to this thread so thought not to start a completely new one.

I am only using a Tigo's RSD, no optimizers or anything, just RSD. the 2F version for 2 modules. Question, do I need any accompanying receiver or anything in addition to the EG4 18PKV? Or do I just install the RSDs on the modules and continue the wiring into the PV inputs wihtin the inverter and the 18KPV takes care of it from there? (crossing my fingers it's that simple)

 

[FilterGuy]

@FilterGuy , you've helped respond to my questions in the past and I have questions similar to this thread so thought not to start a completely new one.

I am only using a Tigo's RSD, no optimizers or anything, just RSD. the 2F version for 2 modules. Question, do I need any accompanying receiver or anything in addition to the EG4 18PKV? Or do I just install the RSDs on the modules and continue the wiring into the PV inputs wihtin the inverter and the 18KPV takes care of it from there? (crossing my fingers it's that simple)

It is that simple.

The 18Kpv has the transmitter built in and it should work well with your receivers.

 

[Jdcarrol]

It is that simple.

The 18Kpv has the transmitter built in and it should work well with your receivers.

Wow, I just found another thread you started and asked there too. Your support has been phenomenal, thanks for what you give the community.

 

[FilterGuy]

BTW: Here is a bonus for you:

A lot of people who add RSD to an inverter end up powering the RSD transmitter from the AC out of the inverter. This mostly works. Where it breaks down is when the battery runs low and the inverter shuts off power in the middle of the night. At that point, the transmitter is powered down and the panels are disabled. The next morning the sun is up and the birds are singing but the panels are still disabled. The system does not turn back on even though there is plenty of sun. There has to be some kind of manual intervention to get things working again. (This is known as the dark-start problem).

The 18Kpv will shut down the AC output while the batteries still have a little left in them. This means that the integrated transmitter stays on and the next morning the panels are operable so the batteries start charging again.

 

[Jdcarrol]

Good morning @FilterGuy , we’ve been up and running for a couple weeks now. We have 3 PV strings. PV string no2 is working but strings 1 and 3 are not.

I had a solar electrician come out and test things out. He said he’s getting one amp per RSD module on the strings, each string has 10PV modules and 5 RSDs (1 Tigo rsd per two PV modules). Because of this, he’s saying we need to get the Tigo rsd transmitter even though the 18kPV should have it on its own. Thoughts?

 

[FilterGuy]

Good morning @FilterGuy , we’ve been up and running for a couple weeks now. We have 3 PV strings. PV string no2 is working but strings 1 and 3 are not.

I had a solar electrician come out and test things out. He said he’s getting one amp per RSD module on the strings, each string has 10PV modules and 5 RSDs (1 Tigo rsd per two PV modules). Because of this, he’s saying we need to get the Tigo rsd transmitter even though the 18kPV should have it on its own. Thoughts?

>He said he’s getting one amp per RSD module on the strings,

I am not sure what that means. Does that mean he is getting a total of 5 amps on each string?
What voltage is he getting at the PV connections to the inverter?

 

[fromport]

I had a solar electrician come out and test things out. He said he’s getting one amp per RSD module on the strings,

Don't you mean 1 Volt per RSD ?
When an RSD device is not enabled it will give roughly 1 volt per device.
In your case 10 panels/RSD devices in series so the input of your inverter you should see 10 Volt.

 

[Quattrohead]

Don't you mean 1 Volt per RSD ?
When an RSD device is not enabled it will give roughly 1 volt per device.
In your case 10 panels/RSD devices in series so the input of your inverter you should see 10 Volt.

No, you will actually see about 1.6-3.2 volts when the RSD is shut down regardless of how many RSD modules.

 

[millsan1]

FWIW, I have the TIGO Optimizers attached to my 18 KPV and they work great.

 

[fromport]

No, you will actually see about 1.6-3.2 volts when the RSD is shut down regardless of how many RSD modules.

Are you sure ?
When I installed a couple of solaredge inverters, each PV module had an optimizer and when I had 10 optimizers in series I would measure something like 10 volt in total at the end when the inverter was turned off.

According to the spec sheet of TS4-A-F

Without a keep alive signal, the standby/resting voltage per MLPE is .6 V

Source: https://support.tigoenergy.com/hc/e...for-Rapid-Shutdown-using-TS4-A-F-and-TS4-A-2F

Pretty sure if you have 10 RSD devices in series you get 10 x 0.6 volt at the end.

 

[kennyb]

FWIW, I have the TIGO Optimizers attached to my 18 KPV and they work great.

Which model do you have? Ts4-o. Or the older ts4-r-o?

 

[millsan1]

Which model do you have? Ts4-o. Or the older ts4-r-o?

ts4-0