RESIDENTIAL PV + BESS
Compatibility Checklist
Many excellent solar arrays under-deliver once an owner decides to “add a battery later.”Almost always the root cause is simple: battery and inverter were never checked for real-world compatibility beyond the headline power rating. Here are ten quick, non-geeky questions you can run through before you sign a purchase order. They focus only on the storage side of the project, so your future self won’t discover that the shiny new pack can’t talk—or even connect—to the inverter you chose.
10 things to double-check before you marry a battery to an inverter
1. “Is my inverter actually hybrid?”
A standard PV string inverter has no battery port at all—adding storage later means paying for a second, AC-coupled inverter or ripping out the first.
2. “Does the battery’s voltage window sit inside the inverter’s?”
Lithium stacks that drop below ~180 V during discharge will force many 8 kW hybrids to throttle—or shut off—long before they’re empty.
3. “Can the inverter’s battery port amps keep up?”
If the BMS allows 50 A but the inverter caps at 25 A, you’ll never hit the advertised backup power; the bottleneck is the lower number.
4. “Which two wires—CAN or RS-485—will carry the data?”
Both use the same twisted pair, but CAN has built-in error checking and multi-master control that most modern BMSs.
5. “Do the two devices speak the same language on that wire?”
Look for an open protocol like SunSpec 800, the industry-standard Pylontech frame set, or an inverter menu that says ‘Self-adapt BMS’.
6. “Is my battery brand listed in the inverter’s compatibility PDF?”
A quick download from the manufacturer saves you from ‘COMM ERR’ alarms and voided warranties.
7. “Can the inverter load a custom CAN map if my brand isn’t yet listed?”
Some hybrids let you import a simple CSV or DBC file; others lock you into a short whitelist. Ask before you buy.
8. “How much power will I really get when it’s cold or hot?”
Temperature changes battery voltage; too low and you drop out of the inverter’s sweet spot, too high and charge current may be cut for.
9. “If I already have a non-hybrid inverter, should I go AC-coupled or replace it?”
AC-coupled batteries retrofit easily but add another inverter stage (≈ 3 % losses) and cost more up-front; swapping to a hybrid may be cheaper.
10. “Is the system set up for closed-loop control?”
When battery and inverter exchange live limits over CAN, round-trip efficiency rises a few percent and full charges finish 20-25 %.
Why these ten save money and headaches
Clashing voltages blow fuses; mismatched protocols raise “battery not detected” alarms; undersized current ratings leave owners wondering why their 10 kWh pack can only run the kettle and not the heat pump. Every issue above has shown up in real installations—sometimes only after scaffolding had come down. A 15-minute desk check beats a multi-day site revisit every time.
Need a second pair of eyes?
GRIDSPHERE specialises in PV + BESS interoperability. Whether you’re wrangling datasheets, planning an upgrade to an existing array, or just want a sanity check before the delivery truck rolls in, we can help.
👉 Drop a note to info@gridsphere.energy and let’s make sure your battery talks—and delivers—right out of the box.
