Knowledge for installers

Answers to frequently asked questions


You are an installer and have technical questions about installation, commissioning and maintenance? Here you will find answers to frequently asked questions about our storage systems.

You can also see instructions, technical documentation and certificates in our download area.


1. Do I need solar irradiation for the commissioning of a DC-coupled RCT Power storage system, and if so, what is the minimum power required?

Yes, you need solar irradiation. A minimum of 100 watts is required.


2. Can I commission an RCT Power storage system in the evening or rather without solar irradiation?

AC-coupled systems can be commissioned without solar irradiation. DC-coupled systems require a minimum power of 100 watts during commissioning. Their internal electronics are supplied from the DC side.


3. What is the maximum time allowed between installation (delivery) and commissioning so that the battery does not discharge itself too much?

6 months from delivery from the RCT Power warehouse. The self-discharge is less than 1% of the capacity per month.


4. Which tool can I use to commission the RCT Power Storage systems?

To commission RCT Power storage systems a mobile device with an Android operating system and the latest version of the RCT Power App is required.


5. How do I connect the Power Storage System with the RCT Power Sensor?

Clamp the three current transformers over each phase conductor leading to the consumption meter of your house connection. Then clamp the control unit into the top hat rail of the subunit. Now run a data cable with RJ45 connectors from the control unit to the RCT Power Storage. That's all! You don't have to set the RCT Power Sensor parameters nor do you need to consider current direction and phase position. You need four subunits for the sub-distribution. With a distance of 20- 30m between RCT Power Storage and RCT Power Sensor you have all the flexibility you need.


6. The RCT Power Sensor operates on the current loop principle, i.e. an analogue signal is processed and transmitted. Is this correct?

This is correct. The RCT Power Sensor transmits analogue values back to the inverter for all measured currents. The RCT Power Sensor is connected to the inverter by a separate cable (Maximum permitted length is 30m).


7. The RCT Power Sensor is not tuned, or the house load shows no or the wrong power values.

There can be several reasons for these scenarios:

  • If the battery is already activated, charging the battery takes priority, and the system will require at least 10% SoC to tune the sensor.

  • No zero feed-in must be configured before the sensor is tuned.

  • The RS485 working mode of the inverter must not be set to "Modbus master".

  • The network mode of the inverter must not be set to "Slave".

  • None of the Digital I/Os must be set to "Input S0 household power".


LED light

1. The battery LED is not lighting up. What do I need to do?

  • Check that the CAN cable from the inverter to the BMS is properly plugged into the corresponding ports. Ensure that you do not use a crossover cable to connect.

  • Check that the internal battery circuit is correctly closed and that all DC connectors are applied properly and in the correct position.

  • If the inverter was malfunctioning and depending on the fault, the fuse could have tripped.


2. What do the different battery LED indicator states stand for?

static orange light:
"Startup" - a connection to the battery is established, and the inverter is running through the test procedure.

static green light:
"In Operation" - the battery is connected and currently operating error-free.

static red light:
The battery is connected but reports an error. Check the "HISTORY" tab in the RCT Power App for errors that begin with BAT_INTERN.

alternate blinking red/green:
Updates for the BMS or the slaves (battery modules) are in process.

alternate blinking orange/red:
The CAN communication between the inverter and the BMS is faulty or without function. Check the connecting cable between the two devices.



It will load necessary cookies, Google Fonts, Google Maps, OpenStreetMap, Youtube and Google Analytics. More details in our privacy policy and our imprint.