Node-3 LV Wiring

Click any component label to highlight its wires + destinations · click again or click background to reset
Node-3 bench Red 12V+ · MEAN WELL→WAGO Red 12V+ → SSR OUT+ common Red 12V+ → E-stop NC in Red 12V (E-stop NC out) → Yazaki Pin1 Black GND · MEAN WELL→WAGO Black GND → SSR OUT− Black GND → Yazaki Pin2 Grn/Yel PE earth → chassis Orange GPIO 21(pre)/17(neg)/48(pos) → SSR IN+ [26-pin underside header] Orange coil Ch1/2/3 → Yazaki Orange USB /dev/ttyUSB0 ⛔ REMOVED — no Pi→T-2CAN CAN wire needed White CAN-B-H → Yazaki CAN-H (LEAF BMS) ✔ CORRECTED White RS485-A (JZK dongle→FoxESS) ⛔ REMOVED — no Pi→T-2CAN CAN wire needed Blue CAN-B-L → Yazaki CAN-L (LEAF BMS) ✔ CORRECTED Blue RS485-B (JZK dongle→FoxESS) E-STOPNC contactin series 12V TOMZN DC breakersHV side - no LV wiring ③ MEAN WELL HDR-60-12⑤ SSR-04 - coil relayE-STOP NC (click=wires)① Pi 4B (PoE) + ⑥ Waveshare HAT④ LilyGo T-2CAN (DALA)⑦ WAGO junctions⑧ Yazaki 36-pin harness Click a label on the photo to highlight its wires and destinations - click again to resetRed 12V+Black GNDGrn/Yel EarthWhite CAN-H/RS485-ABlue CAN-L/RS485-BOrange GPIO/coil - dashed=USBjunction dot / cable tie mark shown120Ω CAN terminator (3 off — install before powering) ⛔ WRONG — T-2CAN CAN-A-H → FoxESS BAT CAN direct (no Waveshare) ⛔ WRONG — T-2CAN CAN-A-L → FoxESS BAT CAN direct (no Waveshare) Orange USB /dev/ttyUSB1 → JZK dongle PoE ethernet 5V → Pi 4B power GND bond · WAGO→LilyGo (PoE/USB↔12V ref) 120 Ω CAN-A term 120 Ω CAN-B term 120 Ω CAN-A FoxESS term
✔ Inventory confirmed 8 Sep 2026
Mean Well HDR-60-12 · SSR-04 · E-stop NC mushroom · TOMZN DC breakers · Pi 4B + Waveshare 2-CH CAN HAT (optional, not in main DALA path) · JZK USB-RS485 dongle · LilyGo T-2CAN · WAGO connectors · Yazaki 36-pin harness
⚠ Still needed: 3× 120Ω resistors (CAN terminators: CAN-A LilyGo end, CAN-A FoxESS end, CAN-B LilyGo end — pack self-terminates at BMS end, no 4th needed)

③ MEAN WELL HDR-60-12

TerminalWireTo
+VRed 4mm2WAGO 12V bus
-VBlack 4mm2WAGO GND bus
PEGrn/Yel dashedLeft rail to chassis earth

② JZK USB-RS485 to FoxESS (Modbus RTU)

USB dongle on Pi USB port - NOT the Waveshare CAN HAT
JZK terminalWireFoxESS COM
A+Yellow/WhitePin 1 RS485-A
B-BluePin 2 RS485-B
GNDBlackPin 3 GND
/dev/ttyUSB1 - addr 247 (0xF7) - 9600 N81

④ LilyGo T-2CAN - DALA BMS gateway

PinWireTo
CAN-B H/L ✔White/BlueYazaki CAN-H/L Pack 1 ← LEAF battery BMS (corrected: was CAN-A)
CAN-A H/L ✔White/BlueFoxESS BAT CAN port — direct, no HAT needed (T-2CAN already isolated)
IO21/IO48/IO17 ✔OrangeSSR-04 IN+ Ch1=IO21(row10,precharge) / Ch2=IO48(row9,+cont) / Ch3=IO17(row11,−cont) — UNDERSIDE 26-pin expansion header RIGHT column: row9=IO48=+POS, row10=IO21=PRE, row11=IO17=−NEG, row12=GND. Solder wires to pads or fit 2×13 2.54mm header + Dupont.
GND (contactor ref)BlackSSR-04 IN− common — UNDERSIDE header RIGHT column row 12 (GND, immediately below IO17 NEG pad)
RS485 SH port (top)White4-pin SH-1.0mm → RS485 TTL module → Pi /dev/ttyUSB1 → FoxESS Modbus (GPIO43=TX, GPIO44=RX)
USB (data + 5V pwr)Orange dashedPi /dev/ttyUSB0 · LilyGo powered from Pi USB 5V

⑤ SSR-04 - contactor coil switching

TerminalWireTo
IN+ Ch1 (precharge)OrangeLilyGo IO21 — underside 26-pin R.col row 10
IN+ Ch2 (+cont)OrangeLilyGo IO48 — underside 26-pin R.col row 9
IN+ Ch3 (−cont)OrangeLilyGo IO17 — underside 26-pin R.col row 11
IN− (shared)BlackLilyGo GND — underside 26-pin R.col row 12
OUT Ch1 terminal ARed12V+ from WAGO 12V bus
OUT Ch1 terminal BCyanPin 7 CT_PRE+ [Cyan] → all 3 Yazakis (daisy)
OUT Ch2 terminal ARed12V+ from WAGO 12V bus
OUT Ch2 terminal BPurplePin 15 CT_POS+ [Purple] → all 3 Yazakis (daisy)
OUT Ch3 terminal ARed12V+ from WAGO 12V bus
OUT Ch3 terminal BOrangePin 18 CT_NEG+ [Orange] → all 3 Yazakis (daisy)
✔ No shared OUT−. Each channel is a relay contact: 12V on one terminal, coil+ on the other. Coil− (Pin 8 [Blue], Pin 16 [Green], Pin 19 [White]) go directly to GND bus — NOT through the SSR.
E-stop NC in series: WAGO 12V → E-stop → PIN1/IGN BUS → Yazaki Pin 1 [Red,BAT] AND Pin 2 [Yel/Grn,IGN] on all 3 packs. Both must drop simultaneously.

⑦ WAGO 12V / GND distribution

✔ DROK 12V→5V buck — NOT FITTED. Pi powered by PoE injector; LilyGo by Pi USB 5V.
BusFeeds
12V+SSR OUT+ (coil supply) · E-stop NC out → PIN1/IGN BUS → Yazaki Pin 1 [Red,BAT] + Pin 2 [Yel/Grn,IGN] on all 3 packs
GNDYazaki Pin 8 [Blue] CT_PRE− · Pins 10/11 [Black] · Pin 16 [Green] CT_POS− · Pin 19 [White] CT_NEG− (all coil − wires go direct to GND — NOT through SSR) · GND bond → LilyGo for PoE↔12V ground reference. Pin 2 is NOT GND — it is IGN +12V.

⑧ Yazaki 36-pin harness

PinWireSourcePacks
Pin 1 BAT +12V [Red]RedPIN1/IGN BUS via E-stop NCAll 3
Pin 2 IGN +12V [Yel/Grn]Yel/GrnPIN1/IGN BUS via E-stop NC (same as Pin 1) — NOT GNDAll 3
Pin 7 CT_PRE+ [Cyan]CyanSSR Ch1 OUT [IO21]All 3
Pin 8 CT_PRE− [Blue]BlueWAGO GND busAll 3
Pins 10/11 GND [Black]BlackWAGO GND busAll 3
Pin 15 CT_POS+ [Purple]PurpleSSR Ch2 OUT [IO48]All 3
Pin 16 CT_POS− [Green]GreenWAGO GND busAll 3
Pin 18 CT_NEG+ [Orange]OrangeSSR Ch3 OUT [IO17]All 3
Pin 19 CT_NEG− [White]WhiteWAGO GND busAll 3
Pin 4 CANL [Grey]GreyLilyGo CAN-B LPack 1 only
Pin 5 CANH [Brown]BrownLilyGo CAN-B HPack 1 only
All other pins: DO NOT CONNECT. Pins verified from physical custom cable map Sep 2026. Packs 2/3 CANL/CANH (Pins 4/5) may optionally connect to Pi Waveshare Ch1/Ch2 for monitoring — see section below.

① Pi 4B + ⑥ Waveshare 2-CH Isolated CAN HAT (optional Pack 2/3 monitor)

✔ Waveshare 2-CH Isolated CAN HAT: NOT in DALA path. Connects to Pi GPIO header only. Used to monitor Pack 2 and Pack 3 CAN independently — hardware_bridge.py parses raw BMS CAN frames. Waveshare is optocoupler-isolated so electrically safe.
✔ Pi 4B powered via PoE injector → RJ45 ethernet (not from 12V bus)
⚠ CAN termination: LilyGo CAN-B 120Ω at LilyGo end. LilyGo CAN-A 120Ω at LilyGo end + 120Ω at FoxESS end. Waveshare Ch1/Ch2 120Ω at Pi end (each channel — BMS provides far end). Do NOT bridge Waveshare into LilyGo or FoxESS signal path.
ChannelWireToNote
Ch1 (CAN0) H/LGrey/BrownPack 2 Yazaki Pin 4 CANL [Grey] / Pin 5 CANH [Brown]Optional — Pack 2 monitoring. 120Ω at Pi end.
Ch2 (CAN1) H/LGrey/BrownPack 3 Yazaki Pin 4 CANL [Grey] / Pin 5 CANH [Brown]Optional — Pack 3 monitoring. 120Ω at Pi end.
dtoverlay=mcp2515-can0,oscillator=16000000,interrupt=25
dtoverlay=mcp2515-can1,oscillator=16000000,interrupt=24
ip link set can0 up type can bitrate 500000