Tesla Model 3 Battery with Deye SUN Inverter

Deye SUN-K-SG01HP3 three-phase hybrid inverters are aggressively priced, well-supported by the DIY community and cover the full 5–50 kW range that a single or multiple Tesla Model 3 packs can serve. This page documents both product families supported through the BMS-EV controller: the AM2 series for residential 5–20 kW and the BM3 series for commercial 29.9–50 kW.

Direct answer. A complete Tesla Model 3 (or Model Y) pack pairs with the Deye SUN-(5–20)K-SG01HP3-EU-AM2 for small residential systems and with the SUN-(29.9–50)K-SG01HP3-EU-BM3 for larger commercial installations, through the BMS-EV controller. The original Tesla BMS is retained. The BMS-EV controller sits on the internal CAN bus at 500 kbit/s and re-encodes the Tesla proprietary telemetry into Deye's native low-voltage-style protocol (a Pylontech-derived dictionary that Deye adopted for its high-voltage battery interface). Tesla's 270–410 V window sits inside Deye's wide 160–800 V input range, so both LR NCA and LFP variants operate across their full BMS-defined SoC range.

What works, at a glance

All Model 3 pack variants: LR NCA, SR+ NCA, SR+ LFP, Highland refresh.
Model Y AWD / LR / Performance (shared pack architecture).
Deye SUN-5K/6K/8K/10K/12K/15K/16K/20K-SG01HP3-EU-AM2.
Deye SUN-29.9K/30K/40K/50K-SG01HP3-EU-BM3.
Grid codes: VDE-AR-N 4105, EN 50549, G99, CEI 0-21, NC RfG, C10/11 (Belgium), CQC (China).
Backup output (Load port) up to full inverter rated power, single or three-phase unbalanced.
Parallel operation: up to 10 units on AM2, up to 6 units on BM3.

Two Deye product families — AM2 vs BM3

Deye splits its three-phase hybrid line into two hardware families that are electrically and mechanically different despite sharing the SUN-K-SG01HP3 naming convention. Choose based on total power and installation type.

Family	Power range	Typical use	DC input range	MPPT trackers	PV oversizing	Battery ports
AM2 series	5–20 kW	Residential single-home	160–800 V	2 (5–8K), 3 (10–20K)	1.3–1.5×	1 HV battery bank
BM3 series	29.9–50 kW	Commercial, farm, small industry	180–800 V	3 (all)	1.3×	1 or 2 HV battery banks

Supported Deye AM2 models (residential 5–20 kW)

Model	AC power	Backup output	Max PV	Notes
SUN-5K-SG01HP3-EU-AM2	5 kW	5 kW / 20 A	7.5 kWp	Smallest single-family option.
SUN-6K-SG01HP3-EU-AM2	6 kW	6 kW / 25 A	9 kWp	Common EU residential.
SUN-8K-SG01HP3-EU-AM2	8 kW	8 kW / 33 A	12 kWp	Standard family home.
SUN-10K-SG01HP3-EU-AM2	10 kW	10 kW / 40 A	15 kWp	Most popular BMS-EV pairing in DE / NL.
SUN-12K-SG01HP3-EU-AM2	12 kW	12 kW / 50 A	18 kWp	Larger villa with heat pump.
SUN-15K-SG01HP3-EU-AM2	15 kW	15 kW / 63 A	22.5 kWp	3-phase heat pump + EV charger.
SUN-16K-SG01HP3-EU-AM2	16 kW	16 kW / 65 A	24 kWp	Slightly higher continuous rating than 15K.
SUN-20K-SG01HP3-EU-AM2	20 kW	20 kW / 82 A	30 kWp	Small workshop, large home with EVs.

Supported Deye BM3 models (commercial 29.9–50 kW)

Model	AC power	Backup output	Max PV	Notes
SUN-29.9K-SG01HP3-EU-BM3	29.9 kW	29.9 kW	39 kWp	Sized to stay below AT/DE 30 kW grid limits.
SUN-30K-SG01HP3-EU-BM3	30 kW	30 kW	39 kWp	Farm / small commercial.
SUN-40K-SG01HP3-EU-BM3	40 kW	40 kW	52 kWp	Medium commercial.
SUN-50K-SG01HP3-EU-BM3	50 kW	50 kW	65 kWp	Largest single-inverter. Requires ≥ 2 Tesla packs for sustained discharge.

Minimum Deye firmware: ARM 1.5.6.6 / DSP 1.4.0 for AM2, ARM 1.5.6.4 / DSP 1.3.4 for BM3. Both families accept "HV battery" mode and expose the compatible protocol dropdown that includes "BYD HVS", "Pylontech HV" and "Deye HV Native" — BMS-EV emulates the latter for the closest match to Deye's internal state machine.

Battery voltage range — Tesla 270–410 V vs Deye 160–800 V

Deye's wide 160–800 V DC input range is one of the reasons this inverter family is so forgiving of second-life batteries. Both Tesla chemistries fit comfortably:

Model 3 LR NCA (270–410 V): full pack voltage window is inside Deye's operating range. BMS-EV enforces a working window of 300–405 V, giving ~70 kWh usable on a healthy 75 kWh pack.
Model 3 SR+ LFP (212–383 V): even the deeply discharged LFP is well above Deye's 160 V floor. Usable window is 320–383 V, roughly 45 kWh out of the 60 kWh nominal, with excellent cycle life.
Model 3 Highland LR (270–410 V): identical window to legacy LR NCA. No changes to inverter configuration.

Because Deye's DC input starts at 160 V (whereas SOFAR HYD nominal window starts at 350 V for optimal efficiency), LFP packs perform much better on Deye — you get more of the pack's nominal capacity into the usable window.

CAN protocol — Tesla native to Deye HV

Deye uses a superset of the Pylontech HV protocol with proprietary extensions for BMS status, alarm codes, force-charge requests and firmware version reporting. BMS-EV firmware translates the Tesla dictionary into Deye's native format on CAN2 at 500 kbit/s.

Deye CAN ID	Purpose	Source in Tesla data
0x351	Battery limits (charge/discharge V and I)	Computed from Tesla cell V and T
0x355	SoC and SoH	Tesla 0x212 (SoC), estimated SoH from voltage vs coulomb-counted energy
0x356	Pack voltage, current, temperature	Tesla 0x132, 0x312
0x359	Alarms and warnings bitmask	Derived from Tesla status flags
0x35A	Battery bank identity (BMS-EV signature)	Constant, identifies as "BE-TESLA3"
0x35E	Manufacturer name string	"BMS-EV" (Deye displays as battery brand)
0x35F	Battery model and firmware version	Firmware version from BMS-EV, model "M3-LR" / "M3-LFP" / "M3-HL"
0x372	Cell count, module count, temp sensor count	Static per pack variant
0x373	Cell voltage min/max + temperature min/max	Tesla 0x352 (cell V), 0x312 (T)

Charge and discharge current limits sent on 0x351 are dynamically computed by the BMS-EV controller:

NCA: CCL derates from 50 A at 3.9 V/cell to 0 A at 4.10 V/cell; DCL derates from 200 A (or inverter max) at 3.6 V/cell to 0 A at 3.2 V/cell.
LFP: CCL derates from 60 A at 3.35 V/cell to 0 A at 3.55 V/cell; DCL derates from 200 A at 3.15 V/cell to 0 A at 2.85 V/cell.
Both chemistries: CCL = 0 below 0 °C, DCL = CCL = 0 above 55 °C.

Wiring architecture

┌───────────────────────────┐ │ Tesla Model 3 pack │ │ 350 V nominal │ └──────┬──────────┬─────────┘ │ HV+/HV− │ LV connector (CAN, wake, HVIL) │ │ │ ▼ │ ┌──────────────┐ │ │ BMS-EV │◄── 12 V aux │ │ controller │ │ └──────┬───────┘ │ │ CAN 500 kb (Deye HV) │ │ │ ▼ │ ┌──────────────┐ └──►│ Deye SUN │◄── PV strings │ 10K-SG01HP3 │ │ -EU-AM2 │ └───┬──────┬───┘ │ │ Grid port Load port (backup) │ │ Grid Critical loads

Installation requirements

Engineering values below are examples. Final conductor cross-section and protective-device sizing must be calculated for the actual pack, maximum current, cable length, installation method, ambient temperature and applicable local standards (IEC 60364-7-712, VDE-AR-N 4105, NEC 690).

HV DC cabling. 25 mm² up to SUN-15K-AM2; 35 mm² for 16–20K-AM2; 50 mm² for 29.9–40K-BM3; 70 mm² for 50K-BM3. Orange sheath, 105 °C rated.
DC fusing. gPV HRC fuses: 100 A (5–10K), 160 A (12–20K), 250 A (29.9–40K), 315 A (50K).
Communication. Twisted pair, RS485/CAN COM port on Deye's BAT-COM connector (RJ45 pinout — pin 4 CAN-H, pin 5 CAN-L). Deye's terminator DIP switch must be set to ON.
Load port wiring. If using backup output, wire critical loads to the Load port through a dedicated changeover contactor (Deye handles the transfer internally < 20 ms).
Neutral bonding. AM2 requires a bonded neutral in backup mode. BM3 has software-selectable neutral bonding. Follow local wiring code.
Grounding. Pack case bonded to main equipotential bar with 16 mm². Inverter chassis grounded independently.
CT clamps. Deye ships three CT clamps to measure grid import/export. Install on the grid feed, not on the inverter output. Correct CT polarity is critical for self-consumption logic.
Clearance. AM2 needs 300 mm clearance top/bottom, 200 mm sides. BM3 needs 500 mm top, 300 mm sides.

Commissioning sequence

Verify HVIL closed and pack terminal voltage 280–410 V with DC isolator OPEN.
Power on the BMS-EV controller (12 V aux). Wait for 1 Hz green LED = pack CAN OK.
On the Deye display: Settings → Battery Settings → Battery Type = "Lithium", Protocol = "00" (Deye native / Pylontech HV), Battery Capacity = the value shown on the controller config screen (typically 200 Ah for LR NCA per pack).
Set charge/discharge voltages: leave defaults, they are overridden by the BMS on CAN.
Close DC isolator. Controller commands precharge, then main contactors close within 4–6 s.
Deye display should show battery online with SoC, V, I updating at 1 Hz.
Trigger a test discharge by forcing a load; verify Deye's "Battery Discharge Power" matches the inverter's AC output within the inverter's own ~2% accuracy.

Known limitations

Deye AM2 firmware older than ARM 1.5.6.6 shows sporadic "BAT COM FAIL" alarms with Tesla-emulated batteries because it expects a heartbeat every 500 ms. BMS-EV firmware 9.2.0 changed the default heartbeat to 250 ms to accommodate this; ensure your controller firmware is current.
Deye BM3 with two battery banks: the second battery port cannot be daisy-chained to the same Tesla pack. Use two independent Tesla packs, two BMS-EV controllers, and two CAN buses (BAT1 and BAT2 on the inverter).
Parallel operation. When paralleling multiple Deye inverters, each inverter must have its own battery bank. Multi-inverter one-battery topology is not supported.
Deye's "Force charge" function ignores CCL if the SoC is below the "Battery Empty" setpoint. Set this at 5% or higher to avoid the Tesla BMS opening contactors under a forced-charge attempt into a cold pack.
LFP low temperature. LFP packs have very poor low-temperature charge behaviour. Below 5 °C, plan for pack heaters or accept CCL = 0 (self-consumption still discharges normally down to −10 °C).
Grid outage transient. AM2 has a < 20 ms transfer to backup. BM3 is < 100 ms. Sensitive loads (older CRT TVs, some medical equipment) may still see the dropout — use an inline online UPS if needed.

Frequently asked questions

Which Deye protocol should I select on the display?

Select protocol code "00" (Deye native / Pylontech HV). BMS-EV firmware emulates this dictionary. Do not select "01" (BYD HVS) — while it also connects, the SoC reporting is slightly less accurate for the Tesla mapping.

Can I mix a Tesla pack with a factory battery on the same Deye inverter?

Not on AM2 (single bank). On BM3 you can put a factory battery on BAT1 and a Tesla pack on BAT2, or vice versa, but the inverter will treat them as two independent banks with their own SoC — it will not homogenise them. Contact us before ordering for BM3 mixed-bank support.

How much backup runtime does a Model 3 LR pack give on a Deye SUN-10K?

~65 kWh usable ÷ typical 2 kW backup load = ~32 hours. At 5 kW critical load: ~13 hours. Longer than any factory home battery, because you are starting from a full EV pack.

What is the round-trip efficiency?

Measured 88.5% AC-to-AC at 5 kW on SUN-10K-AM2, 87% at 10 kW. AM2 is slightly less efficient than BM3 at high load; BM3 approaches 90% at 20 kW.

Can I read pack data over Modbus?

Yes. Deye exposes full battery telemetry (SoC, cell V, T, current, alarms) via its Modbus/TCP interface (built-in dongle) or Modbus/RS485. Registers are documented in Deye's protocol manual. The BMS-EV controller does not need to be queried separately.

Does the Deye zero-export feature work with the Tesla pack?

Yes. Zero-export uses the grid CT clamps and the AC-side control loop; the battery type is irrelevant. The Tesla pack absorbs excess PV instead of feeding the grid, up to the pack's CCL.

Can a single Deye SUN-50K-BM3 handle only one Tesla pack?

Electrically yes, but you will hit the pack's 350 A continuous discharge limit (~120 kW) well below the inverter's 50 kW peak — no problem. However, cycling one pack at up to 50 kW discharge is aggressive; two paralleled packs give better thermal margin and lifetime.

What happens during a grid fault (island transition)?

Deye detects grid loss within 40 ms (AM2) or 80 ms (BM3), opens the grid contactor, and continues to power the Load port from PV + battery. The battery discharge current limit is the same in island mode as in grid-tied mode. The BMS-EV controller sees no change on its side — the pack is unaware of the island transition.

Order a Tesla Model 3 + Deye SUN controller

Pre-flashed for SUN-K-SG01HP3-EU-AM2 (5–20 kW) or BM3 (29.9–50 kW)

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Last updated: 2026-09-18

Current firmware: 15.0.14

Technical author: BMS-EV engineering team (Clima Boost sp. z o.o., Poland)

Reviewer: Jakub Lipiński, founder/lead engineer BMS-EV

Revision: 2026-09-18 — aligned with firmware 15.0.14, SOFAR 180–800 V DC verification, Kia EV6 + SOFAR HYD 15KTL case study reference