Recently, our AC Academy hosted a webinar on Sigenstack Commercial inverters and battery systems, providing installers and industry professionals with insights into the system design, installation, and operational considerations. During the session, participants asked a number of great questions. We’ve compiled the most frequently asked ones along with detailed answers to help you better understand Sigenstack solutions.
We’ve also covered the Commercial Battery Modelling Software, which provides performance and financial insights. You can watch Stuart’s presentation here to learn more about our services for commercial modelling: Watch on YouTube
Attention all Sigenergy installers in Australia! Sigenergy strongly urge all installers to complete the technical training they are running today (1st of Oct) via webinar. This training will enable you to get the most out of their products and prevent future rectification work.
- 1–2pm, Wednesday 1st Oct: Register here
- 6–7pm, Wednesday 1st Oct: Register here
Webinar Access and Materials
Q: Can we watch the previous Sigenstor webinar or other previous masterclasses?
A: Yes! The webinar is available on YouTube. You can watch the full SigenStor Design Masterclass here, and our first Sigenergy Technical Masterclass here. Also available through the Smart Installer by the Smart Energy Council
Watch full Sigenstack Session
System Design and Installation
Q: Would there be a combiner to parallel 100 Sigenstack inverters, or do we need to use your Gateway?
A: For a grid-connected system using HYA inverters, an AC combiner or distribution board is required, but no Sigenergy Gateway is needed. For a backup system, the Sigenergy Gateway Controller is required.
Q: Is there a 100kVA Sigenergy Gateway or higher?
A: Using HYB inverters, you can install a 100kVA inverter with backup without a gateway. If you need a generator connection, a custom gateway can be quoted through AC Solar Warehouse.
Q: Can we mix new and old battery modules in a stack over time?
A: Yes, the battery modules are individually optimised, similar to SigenStor, so this is possible.
Q: Is the interconnection between the stacks through sub-bases? What is the spacing?
A: Yes, the stacks are pre-wired through the bases. Spacing is approximately 300mm between each stack.
System Design and Installation in Queensland-Specific Requirements
Q: Do installers need to use the Sigenergy PSC Kit for GSD control in Queensland?
A: Currently, the PSC Kit is required for GSD control in Queensland installations. In the future, if the kit is no longer needed, Sigenergy will advise installers.
Q: What if an installer still uses the PSC Kit after it’s no longer required?
A: There’s no issue—installers can continue to install the PSC Kit. A software option will allow you to select whether the PSC is installed or not, ensuring the system operates correctly regardless.
Learn more here. Download Sigenergy Technical Note
Battery Performance and Controllers
Q: What’s the point of a 1C discharge if the inverter is 125kW max?
A: Different battery controllers are required depending on the number of modules in the system. For example, 20-21 modules require a 0.5C battery controller to handle the current efficiently.
Q: With a 0.5C controller, what peak power can be expected?
A: The peak power is 0.5 times the battery capacity. For example, a 240kWh stack can deliver 120kW continuous.
Q: What is the C-rate of individual battery modules?
A: Each module has a 0.5C nominal rate and 1C maximum rate.
Sensors, Monitoring, and Integration
Q: Do we need to use the Sigenergy Power Sensor?
A: Yes, a power sensor is required for systems without a gateway.
Q: Can we use the residential-grade Wireless Sigen sensor with C & I inverters?
A: Yes. The same power sensors work, and you can use third-party CTs with Sigenergy’s meter, paired with the SUB1G transmitter/receiver for wireless communication.
Q: What standard CT sizes are supported? What about Rogowski coils?
A: Standard CTs and compatible third-party CTs can be used with the existing power sensors.
More SigenStack Questions and Answers:
The following questions and answers were raised through different installer channels outside the webinar. Since many of you may be looking for these answers too, we’ve included them here for your reference.
Sigenergy Warranty Code Activation
Q: A customer has received warranty codes but is having trouble finding where to enter them. Is there a guide or simple explanation?
A: Yes. In the mySigen app, go to System Settings for the relevant site. Scroll to the bottom and navigate to:
Installer Tools → License Activation
Here, the warranty codes can be entered to activate the system’s license.
Sub1G Network Range and Extenders
Q: The Sub1G kit uses an IEEE 802.11ah signal. Can a repeater or router with the same protocol be used as an extender? My customer’s MSB is 200 m away, with trees and sheds causing interference.
A: This hasn’t been formally tested, but some practical experience shows it can work slightly beyond 200 m. For example, a test over 234 m with a thin tree line was successful. R&D has also been asked to trial it.
Recommendation: Test on-site if the installer is willing, as environmental factors like trees and buildings can affect performance.
Generator Interaction and Load Management
Q: If a manual-start generator is running on the Smart Port and the batteries are already full, is this okay? Will the generator just feed the loads until it’s switched off, and the Sigenstor just won’t draw any load?
A: Yes, this is fine from a Sigenstor perspective. The system will not draw power from the generator once the batteries are full—it will only supply the loads. Keep in mind, however, that running a generator under these conditions can be a waste of fuel.
Q: Can a split-phase generator run 2 x 1-phase Sigenstor systems with 1-phase gateways? For example, if one battery is full, can that battery sit idle while the other draws from the generator to charge?
A: Yes, from the Sigenergy perspective, this setup is okay. The system will allow one battery to sit idle while the other draws power. Other considerations, such as whether the generator can handle unbalanced loads, should be evaluated separately.
Communications Module and Data Management
Q: Once the 2-year data period on the comms module is up, is there a way to top up the data, or does the customer need a new module?
A: Customers have two options:
- Top up the SIM via the “Mall” option in the mySigen app.
- Use any compatible SIM at any time, either before or after the 2-year period.
This ensures continuous connectivity and monitoring without needing to replace the comms module.
Metering and Energy Monitoring
Q: Can we meter 2 third-party inverters in different locations using Sigenergy meters? Are either of these part numbers Gen 2 meters, and do we need a second set of CTs?
- Part numbers: Sigen Sensor TP-CT120-DH, Sigen Sensor TP-CT100
A: Yes, you can daisy-chain 2 energy meters via RS485 communications for production monitoring. Assign each meter a different address in the app. You can have a maximum of 5 production sensors on a three-phase system, and 1 consumption sensor. This allows you to measure multiple inverters across different locations.
Q: If the meters aren’t Gen 2, can we use the gateway’s inbuilt meter along with RS485 ports on the energy controller to measure external production?
A: Yes, this is possible. You can use the gateway’s inbuilt meter for import/export and connect external production sensors via RS485-1 and RS485-2 to the energy controller for additional measurements.
Connectivity and Performance
Q: What happens if a Sigenstack system is disconnected from the internet for more than 90 days?
A: After 90 days offline, the system enters safety mode to protect the battery and ensure safe operation. Safety mode includes:
- State of Charge (SOC) operating range limited to 10%–90%
- No short-time overload capacity if cell temperature is below 10 °C or above 45 °C
- Charging power reduced to 70% of rated power
- Discharging power reduced to 70% of rated power when the cell temperature is below 10 °C or above 45 °C
Q: What if the system has intermittent 4G connectivity due to weak signal?
A: Short-term dropouts don’t trigger safety mode. The system only enters safety mode if it’s offline continuously for 90 days or more. For customers with variable 4G coverage, connecting the system whenever possible and performing periodic online checks will prevent throttling.
Key Takeaways from the SigenStack session:
- Flexible design – Works for both grid-connected and backup systems; gateways are only needed for backup or generator setups.
- Scalable performance – Battery controllers (0.5C or 1C) match system size, with 0.5C providing 120 kW continuous from a 240 kWh stack.
- Mix-and-match batteries – New and old modules can be combined in one stack thanks to individual optimisation.
- Simplified installation – Stacks interconnect through pre-wired sub-bases with around 300 mm spacing.
- Versatile monitoring – Supports multiple power sensors, third-party CTs, and RS485 daisy-chaining for flexible metering.
- Reliable connectivity – Sub1G kits can operate beyond 200 m in real conditions, and comms data can be topped up easily via the mySigen app.
- Protected operation – Systems offline for over 90 days enter safety mode with limited SOC and reduced power; short outages don’t affect performance.
- Generator ready – Manual or split-phase generators can safely power loads; systems will not overdraw when batteries are full.
- Queensland compliant – PSC Kits remain required for GSD control; future updates will advise when no longer needed.
- Quick warranty setup – Activate warranty codes via System Settings → Installer Tools → License Activation in the mySigen app.