How to Choose Between CAN and RS485 for Your Solar Battery

April 21, 2026

The 5-Second Answer: CAN vs RS485 – Which One Should You Care About?
CAN vs RS485: The Technical Difference (Simple Version)
Which Inverter Uses CAN and Which Uses RS485? (Compatibility Table)
Why dé Supports Both CAN and RS485 (And Why Most Batteries Don't)
How to Check Which Protocol Your Inverter Needs (3 Methods)
DIY the Communication Cable: Pinout for CAN and RS485
Communication Failed? Step-by-Step Troubleshooting
Frequently Asked Questions About CAN and RS485 for Batteries
Summary

The 5-Second Answer: CAN vs RS485 – Which One Should You Care About?

CAN if you can. RS485 works too. The key is knowing what your inverter needs.

For home energy storage, both CAN and RS485 let your battery and inverter "talk" to each other. But they speak differently.

Think of it this way:

CAN is a smart conference room. Anyone can speak at any time. If two people talk at once, the system automatically decides who goes first based on priority.
RS485 is a classroom with a teacher. Only the teacher (inverter) can ask questions. Students (batteries) wait to be called on.

One sentence to remember:

CAN is "multi-master, anyone can talk." RS485 is "master-slave, only the master can ask."

Here's the reality: If your inverter supports CAN, use CAN. It's faster and more reliable. If your inverter only supports RS485, that's fine too – dé supports both. The key is knowing what your inverter needs and making sure your battery supports it.

Not saying RS485 is bad. It's been around for decades. It's stable, it works, and millions of systems run on it. CAN just has advantages for real-time data like voltage, current, temperature, and state of charge.

CAN vs RS485: The Technical Difference (Simple Version)

You don't need an engineering degree. Four differences are all you need to understand.

Here's what matters for your home solar system:

Feature	CAN	RS485
Speed	Up to 1 Mbps	9600-115200 bps typical (10 Mbps theoretical, but rare in practice)
Distance	Up to 500 meters (1640 feet)	Up to 1200 meters (3937 feet)
Communication Method	Multi-master (any device can start talking)	Master-slave (only the inverter can start)
Collision Handling	Built-in arbitration – automatic	None – software must handle it
Error Handling	CRC check + automatic retransmission	No built-in – relies on higher-level protocols
Cost	Slightly higher ($0.35-0.70 per transceiver)	Lower (simpler overall system)
Use in Batteries	Modern inverters, premium BMS	Older inverters (pre-2018), cost-sensitive systems

What this means for your home:

CAN is better for real-time monitoring. Voltage, current, temperature, SOC – CAN updates faster and more reliably.
RS485 is perfectly fine. If you have an older inverter or you're on a budget, RS485 works. It just might feel slightly slower.

Real-world example: A CAN-connected battery reports SOC changes instantly. An RS485-connected battery might take a few seconds to update. For most homeowners, you won't notice the difference. For off-grid systems with generators or complex energy management, CAN's speed matters more.

Which Inverter Uses CAN and Which Uses RS485? (Compatibility Table)

Check this table. 30 seconds. You'll know which protocol your inverter needs.

Based on dé's official compatibility testing and industry data, here's the breakdown:

CAN Protocol Inverters (partial list):

PYLON, LUXPOWER, Sol-Ark, DEYE, GROWATT, VICTRON, SOLIS, MUST, INVIT, SUNGROW, GOODWE, SOFAR, SOROTEC, SCHNEIDER, SENERGY, SMA, MEGAREVO, TBB, AISIWEI, HOYMILES

RS485 Protocol Inverters (partial list):

PYLON, GROWATT, VOLTRONIC, LUXPOWER, SRNE, SCHNEIDER, EPEVER, PACE

Important – read this:

PYLON and GROWATT appear on BOTH lists. Why? Because different models from the same brand may support different protocols. A Growatt SPF series might use RS485. A Growatt MIN series might use CAN. You MUST check your inverter's manual.

How to check in 30 seconds:

Look at your inverter's label for the model number
Search the manual for "BMS" or "Lithium" or "Communication"
Look for "Protocol" or "CAN" or "RS485"
Still not sure? Try PYLON protocol first – it's the default for both CAN and RS485 on dé batteries.

Why dé Supports Both CAN and RS485 (And Why Most Batteries Don't)

You don't need to guess your inverter's protocol before buying a dé battery. That's the point.

Most battery brands pick one protocol and stick with it. Cheap brands often choose RS485 only (it's simpler and cheaper). Some premium brands choose CAN only (it's newer and faster).

dé chose both.

Here's how dé compares:

Battery Type	CAN Support	RS485 Support	Do you need to know your protocol before buying?
Most budget brands	❌	✅	Yes – or it won't work
Some premium brands	✅	❌	Yes – or it won't work
dé	✅	✅	No – both work

What this means for you:

Already have an inverter? Doesn't matter if it's CAN or RS485. dé works with both.
Planning to upgrade your inverter later? Going from Growatt to Victron? No problem. Switch the protocol on the screen. No new battery needed.
Building a DIY system? You don't need to research protocols before buying. Buy the battery first. Figure out the protocol later.

From dé 5120Wh LiFePO4 Battery:

Supports CAN and RS485 for inverter communication
Supports nearly 30 inverter protocols
PYLON is the default protocol for both
Select CAN or RS485 according to the inverter protocol, then choose the matching inverter model

What's in the box:

CAN communication cable (1000mm / 39 inches)
RS485 communication cable (1500mm / 59 inches)
RJ45 connectors for DIY cable making

Not saying other brands are bad. Many brands focus on one protocol and optimize deeply for it. That's a valid strategy. dé's choice is "compatibility first" – for people who don't want to research protocols before buying a battery.

How to Check Which Protocol Your Inverter Needs (3 Methods)

Spend 3 minutes now. Save 3 hours of troubleshooting later.

Here are three ways to check, from simplest to most thorough.

Method 1: Check the Inverter Label or Manual (Fastest – 5 minutes)

Look for these keywords in your inverter's manual or on the specification sticker:

"BMS port" or "Lithium battery" section
"CAN" or "RS485" mentioned anywhere
"Protocol" or "Communication" parameters
https://www.youtube.com/embed/g8p1FvnPUnY

Real example: Victron manuals explicitly say "CAN-bus BMS LV (500 kbit/s)" for their Cerbo GX devices.

Method 2: Check the Inverter Settings Menu

Navigate through your inverter's display:

Go to battery type settings
Look for "Li BMS" or "Battery Protocol" options
The dropdown menu will show supported protocols

Real example: On Deye/Sunsynk inverters, go to "Battery Type" → select "Lithium" → then "Protocol" shows available options.

Method 3: Look Up Your Brand and Model (Most Accurate)

Use the compatibility table above
Visit your inverter manufacturer's website for technical specs
Still unsure? Email your inverter manufacturer's support

Quick Reference by Era

Inverter Age	Common Protocol	Note
Pre-2018	Mostly RS485	CAN wasn't common yet
2018-2022	Both	Transition period – check manual
Post-2022	Increasingly CAN	New models tend to support CAN

The golden rule: When in doubt, try PYLON protocol first. It's dé's default, and it works on both CAN and RS485.

DIY the Communication Cable: Pinout for CAN and RS485

Wrong pinout = no communication. Here's the right way to do it.

CAN and RS485 use the same RJ45 connector but different pin assignments. Dé provides pre-made cables, but if you need to make your own (custom length, special inverter), here's what you need to know.

dé's RS485 Pinout Definition

From the dé product manual (page 10):

Pin No.	RS485 Definition
1	NC (Not Connected)
2	NC
3	NC
4	NC
5	NC
6	GND
7	RS485-A
8	RS485-B

Important: The manual explicitly says: "The colors of the wires do not matter – just match the pins."

CAN Pinout – No Universal Standard

Unlike RS485, CAN does NOT have a universal pinout standard. Different inverter brands use different pin assignments.

What dé does: The blue CAN communication cable included in the box is pre-wired and tested. Use it out of the box. It works.

If you need to DIY a CAN cable: Your inverter's pinout definition is the final reference. Follow that, not a generic template.

DIY Steps (for RS485)

Only do this if:

Your inverter uses RS485 AND
You need a different cable length (dé includes 1500mm / 59 inches) OR
Your inverter's pinout differs from standard

Steps:

Cut off the RJ45 plug on both ends (if modifying an existing cable)
Crimp a new RJ45 plug following the pinout table above
Ensure Pin 7 (RS485-A) and Pin 8 (RS485-B) are correctly connected
Double-check against your inverter's pinout definition

When You Actually Need to DIY

Situation	Need DIY?
Using dé's included RS485 cable with compatible inverter	No – plug and play
Using dé's included CAN cable with compatible inverter	No – plug and play
Need longer RS485 cable	Yes – or use a coupler
Inverter has non-standard pinout	Yes – follow inverter manual
Using a generic Ethernet cable	Yes – must verify pinout first

Communication Failed? Step-by-Step Troubleshooting

90% of communication failures can be fixed without returning anything. Here's how.

Don't panic. Don't return the battery. Follow these five steps in order.

Step 1: Check Physical Connections (Most Common Issue)

This solves about 50% of problems.

Is the communication cable plugged into the INV port? (Not BIN, not BOUT – those are for battery-to-battery communication)
Is the RJ45 fully inserted? You should hear a click.
Is the cable damaged? Kinks, cuts, or crushed ends?
Is the cable too long? CAN max is 500 meters. RS485 max is 1200 meters. Home installations are fine.

Step 2: Check Inverter Settings

Is the inverter set to "Lithium" or "LiFePO4" battery type? (Not "Lead Acid" or "AGM" or "User Defined")
Is the BMS protocol selected correctly? Look for "PYLON" or "CAN" or "RS485" in the menu.
Some inverters need BMS communication manually enabled. Example: Victron requires DVCC to be turned on.

Step 3: Switch Protocols on the dé Screen

This is dé's unique advantage. Most batteries can't do this.

Go to Protocol Page (screen page 6)
Select CAN or RS485 (based on what your inverter needs)
Choose your inverter model from the list
The button highlights when selected

The dé screen shows:

Battery page (SOC, kWh, kW, V, A)
Cell information page
Warning/protection/error page
Setting page (app pairing, OTA)
Protocol page (CAN/RS485 selection)

Step 4: Restart in the Correct Order (Many People Skip This)

Order matters. Do NOT just turn everything off and on.

Correct power-on sequence:

Turn ON the circuit breaker
Turn ON the battery main switch
Turn ON the inverter

Correct power-off sequence (if needed):

Disconnect all external loads
Turn OFF the battery switch
Turn OFF the circuit breaker

Why this matters: The battery needs to initialize its BMS before the inverter tries to communicate. If the inverter powers up first, it may not detect the battery.

Wait 30 seconds between steps to let capacitors discharge.

Step 5: If Still Not Working

Try PYLON protocol – it's dé's default and works on both CAN and RS485
Try the other communication cable – eliminates cable failure as a cause
Check if your inverter needs a firmware update – some older inverters added CAN support via firmware
Contact dé support: support@depow.com

From dé 5120Wh LiFePO4 Battery:

Screen turns off after 2 minutes of inactivity – tap to wake
Press and hold for 5 seconds to reset Wi-Fi configuration (different issue, but good to know)
The battery can only be linked to one account – not relevant to communication, but FYI

Frequently Asked Questions About CAN and RS485 for Batteries

Q1: Can I use a battery without connecting the communication cable?

Yes, but with trade-offs. The inverter will use voltage-based estimation to guess the battery's state of charge. This is less accurate and can drift over time. For full safety features and accurate SOC, connect the communication cable.

Q2: What happens if I connect CAN to RS485 by mistake?

No hardware damage. The system simply won't communicate. Switch to the correct protocol on the battery screen or change the cable.

Q3: Is CAN always better than RS485 for batteries?

For most home storage applications, yes. CAN offers faster data rates, better error handling, and multi-master capability. But RS485 is still perfectly functional and more common on older inverters (pre-2018). If your inverter only supports RS485, it's fine.

Q4: Does dé support Pylontech protocol?

Yes. PYLON is the default protocol for both CAN and RS485 on dé batteries. This is important because Pylontech is the most widely compatible protocol in the industry.

Q5: How do I know if my inverter is communicating with the battery?

Two ways:

Check the battery screen: it should show SOC (state of charge), voltage, and current
Check the inverter display: it should show battery SOC as a percentage (not voltage-based estimation)

Q6: Can I use a standard Ethernet cable for CAN/RS485 communication?

The physical cable works, but the pinout may differ. Use the included CAN or RS485 cable, or verify the pinout matches your inverter before using a generic cable. Dé includes both cables in the box.

Q7: How many batteries can I daisy-chain with CAN or RS485?

Dé supports up to 16 batteries in parallel using either protocol. However, the training documentation notes that 16 units may have communication latency and cell balancing issues. 10 units is recommended for optimal performance.

Q8: My inverter is not in the compatibility list. What do I do?

Two options:

Try PYLON protocol first – it's dé's default and works with many inverters not explicitly listed
Contact dé support at support@depow.com with your inverter model and protocol documentation

Dé's engineering team maintains a growing compatibility list and can often add support for new inverters.

Q9: What's the difference between INV port and BIN/BOUT ports?

INV port = connects to inverter (for battery-inverter communication)
BIN (Battery In) = connects to previous battery's BOUT port (for parallel setups)
BOUT (Battery Out) = connects to next battery's BIN port (for parallel setups)

For a single battery, only use the INV port. For multiple batteries in parallel, daisy-chain BOUT → BIN between batteries, and connect the first or last battery's INV port to the inverter.

Q10: Does communication work over long distances?

CAN: max 500 meters (1640 feet) – fine for any home installation
RS485: max 1200 meters (3937 feet) – also fine

Your home isn't that big. Distance is not the limiting factor.

Summary

CAN and RS485 both work. CAN is faster and more reliable. RS485 is simpler and more common on older equipment. The key is knowing what your inverter needs.

What makes dé different:

Feature	dé
Supports both CAN and RS485	✅ – no guessing needed
Default PYLON protocol	✅ – most compatible protocol in the industry
30+ inverter protocols supported	✅ – covers most major brands
Screen-based protocol switching	✅ – no computer or special tool needed
Both cables included	✅ – CAN and RS485 cables in the box
Up to 16 batteries in parallel	✅ – expandable storage

The bottom line: You don't need to research inverter protocols before buying a dé battery. It works with both. Plug it in, select your protocol on the screen, and you're done.

Ready to build your system? Check the dé 5120Wh LiFePO4 Battery for compatible inverters and full specifications.

Questions? Contact dé support: support@depow.com

Back to blog

Country/region

Language

Table of Contents