FilterGuy
Solar Engineering Consultant - EG4 and Consumers
I have been investigating Rapid Shutdown on the 18Kpv and would like to offer some clarity on the capabilities and situation.
1) The 18Kpv can do rapid shutdown out of the box using the integrated Rapid Shutdown Initiator. When triggered, the inverter will shut down the AC output and the PV (Shutdown of the PV requires a Sunspec Compliant RSD receiver on the PV panels.)
2) A remote Initiator can be installed on the 18Kpv. EG4 has published a white paper on how to do this. The white paper can be found at:
https://eg4electronics.com/wp-content/uploads/2023/08/External-RSD-Switch-Install-v1.01.pdf
The engineers at EG4 tell me that within a few days, all new shipments of the 18Kpvs will include the ‘Green Connector’ that the paper mentions. In addition, I have been told that Signature Solar Technical support is setting up a process to ship a connector to existing 18Kpv owners on request.
Note: The ‘Green Connector’ mentioned in the paper is not strictly required. However, it simplifies the process because it does not require special crimp or soldering tools.
3) The presence of a PV rapid shutdown system can cause a ‘dark start’ problem if the inverter shuts down when the batteries get low. (The 18Kpv with Sunspec-compliant receivers do not have this issue.) However, when using Tigo Optimizers with the Tigo Cloud Connect Advanced, a dark start problem can happen if the CCA is powered by the Inverter AC output as instructed in the CCA manual. The paper referenced above gives a solution to this problem that was developed by EG4.
Note: There are other optimizers such as the Solar Edge that do not have a known solution to the dark start problem. Take care when selecting your components.
1) The 18Kpv can do rapid shutdown out of the box using the integrated Rapid Shutdown Initiator. When triggered, the inverter will shut down the AC output and the PV (Shutdown of the PV requires a Sunspec Compliant RSD receiver on the PV panels.)
2) A remote Initiator can be installed on the 18Kpv. EG4 has published a white paper on how to do this. The white paper can be found at:
https://eg4electronics.com/wp-content/uploads/2023/08/External-RSD-Switch-Install-v1.01.pdf
The engineers at EG4 tell me that within a few days, all new shipments of the 18Kpvs will include the ‘Green Connector’ that the paper mentions. In addition, I have been told that Signature Solar Technical support is setting up a process to ship a connector to existing 18Kpv owners on request.
Note: The ‘Green Connector’ mentioned in the paper is not strictly required. However, it simplifies the process because it does not require special crimp or soldering tools.
3) The presence of a PV rapid shutdown system can cause a ‘dark start’ problem if the inverter shuts down when the batteries get low. (The 18Kpv with Sunspec-compliant receivers do not have this issue.) However, when using Tigo Optimizers with the Tigo Cloud Connect Advanced, a dark start problem can happen if the CCA is powered by the Inverter AC output as instructed in the CCA manual. The paper referenced above gives a solution to this problem that was developed by EG4.
Note: There are other optimizers such as the Solar Edge that do not have a known solution to the dark start problem. Take care when selecting your components.