CHAdeMO Connector - Pinout, Wiring, CAN Protocol & Complete Specs
Complete guide to the CHAdeMO DC fast charging connector: 10-pin layout, CAN bus communication, V2G capability, power levels up to 400 kW, and the legacy that shaped fast charging.
CHAdeMO Connector. Pinout, Wiring, CAN Protocol & Complete Specs
CHAdeMO. "CHArge de MOve," a pun on the Japanese "o cha demo ikaga desuka" (how about some tea?) suggesting a quick charge while you grab a drink. was the world's first widely deployed DC fast charging standard. Developed by TEPCO, Nissan, Mitsubishi, Toyota, and Subaru starting in 2010, it was fast charging before CCS existed.
For years, CHAdeMO was the only way to DC fast charge in most markets. The Nissan Leaf, the best-selling EV of the 2010s, used CHAdeMO exclusively. At its peak, there were over 40,000 CHAdeMO chargers worldwide.
Today, CHAdeMO is in decline everywhere except Japan. CCS won the standards war in North America and Europe. Nissan switched to CCS for the Ariya in 2022. But CHAdeMO chargers will remain in service for years, and the standard has some genuinely interesting engineering. including the first production V2G (vehicle-to-grid) bidirectional charging system.
Physical layout
CHAdeMO is a DC-only connector. Unlike CCS, it doesn't combine AC and DC in one plug. you need a separate connector for AC charging (Type 1 in Japan/North America, Type 2 in Europe). This means CHAdeMO vehicles have two charge ports: one for AC, one for DC.
The connector is a large, round plug roughly 70 mm in diameter with 10 pins arranged in a distinctive oval pattern.
Rendering diagram...
The two large pins (DC+ and DC–) are at the bottom, clearly larger than the signal pins at the top. The connector has a mechanical locking lever on the side that snaps into the vehicle inlet. a more robust lock than the Type 1 release button, but also bulkier.
Pin assignments
| Pin | Name | Function |
|---|---|---|
| 1 | Charger start/stop signal | Digital signal from charger: "power is on" / "power is off" |
| 2 | Vehicle charge permission | Digital signal from vehicle: "OK to charge" / "stop charging" |
| 3 | Signal ground | Reference ground for the digital signal pins |
| 4 | CAN-H | CAN bus high line (communication) |
| 5 | CAN-L | CAN bus low line (communication) |
| 6 | Charge sequence signal 1 | Part of the plug insertion / connection verify sequence |
| 7 | DC+ | High-voltage DC positive power |
| 8 | DC– | High-voltage DC negative power |
| 9 | Chassis ground | Protective earth / safety ground |
| 10 | Charge sequence signal 2 | Part of the plug insertion / connection verify sequence |
What makes this different from CCS
Two big differences jump out:
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CAN bus instead of PLC: CHAdeMO uses a standard automotive CAN bus (250 kbps or 500 kbps) for communication. CCS uses Power Line Communication over the CP wire. CAN is simpler, lower bandwidth, and uses dedicated wires (pins 4 and 5). PLC is higher bandwidth and shares the CP wire.
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Dedicated start/stop signals: pins 1 and 2 are hardwired digital signals (not CAN messages) that serve as a hardware interlock. The charger physically cannot output power unless the vehicle asserts pin 2, and the vehicle knows power is flowing by monitoring pin 1. This is a belt-and-suspenders safety approach. even if the CAN bus fails, the hardware interlock works.
CAN bus communication protocol
CHAdeMO communication is straightforward compared to ISO 15118. It uses standard CAN 2.0B frames at 250 kbps (CHAdeMO 1.x) or 500 kbps (CHAdeMO 2.0).
Message structure
Rendering diagram...
Key CAN messages
Vehicle → Charger (0x102): sent every 100 ms:
| Byte | Data |
|---|---|
| 0–1 | Target charging voltage (V, big-endian) |
| 2 | Target charging current (A) |
| 3 | Fault flags (battery overvoltage, undervoltage, overcurrent, overtemp) |
| 4 | Battery SOC (%) |
| 5 | Charge enable flag (0x01 = charge, 0x00 = stop) |
| 6–7 | Total battery capacity (0.1 kWh resolution) |
Charger → Vehicle (0x109): sent every 100 ms:
| Byte | Data |
|---|---|
| 0–1 | Available output voltage (V) |
| 2 | Available output current (A) |
| 3–4 | Present output voltage (V, actual measurement) |
| 5 | Present output current (A, actual measurement) |
| 6 | Status flags (charger ready, fault, etc.) |
| 7 | Estimated remaining charge time (minutes) |
That's it. Two main messages, 100 ms update rate, 8 bytes each. Compare that to ISO 15118's multi-layer PLC stack with XML message bodies and TLS encryption. CHAdeMO is refreshingly simple. The downside: no Plug & Charge, no smart charging schedules, no certificate-based authentication.
Charging sequence
Rendering diagram...
Power levels
| CHAdeMO version | Year | Max voltage | Max current | Max power |
|---|---|---|---|---|
| 0.9 | 2010 | 500V | 125A | 62.5 kW |
| 1.0 | 2012 | 500V | 200A | 100 kW |
| 1.2 | 2017 | 500V | 200A | 100 kW |
| 2.0 | 2018 | 1000V | 400A | 400 kW |
| 3.0 (ChaoJi) | Future | 1500V | 600A | 900 kW |
Rendering diagram...
In practice, most deployed CHAdeMO chargers max out at 50 kW (the most common) or 100–150 kW on newer hardware. The 400 kW v2.0 spec exists on paper but virtually no vehicles or chargers supported it before the standard started losing market share.
CHAdeMO 3.0 / ChaoJi
CHAdeMO 3.0 is a joint development between CHAdeMO Association (Japan) and the China Electricity Council (GB/T standard). It's called "ChaoJi" (超级, meaning "super" in Chinese). The goal is a unified next-generation connector for Japan and China that can handle up to 900 kW.
ChaoJi uses a new, smaller connector. not backwards compatible with existing CHAdeMO or GB/T. It's essentially a fresh start. Whether it will gain meaningful traction against CCS in non-Chinese markets is unclear.
V2G. CHAdeMO's killer feature
CHAdeMO was the first standard to support bidirectional power transfer in production vehicles. Vehicle-to-Grid (V2G), Vehicle-to-Home (V2H), and Vehicle-to-Load (V2L) via CHAdeMO have been commercially available in Japan since 2012.
How bidirectional works
The CAN protocol already supports it. the vehicle simply sends a negative current target (or a dedicated "discharge" flag in v1.2+), and the charger reverses power flow. The charger acts as an inverter, converting the car's DC battery power back to AC grid power.
Rendering diagram...
V2G-capable vehicles (CHAdeMO)
| Vehicle | Battery | Max V2G discharge |
|---|---|---|
| Nissan Leaf (all generations) | 24–62 kWh | 6–10 kW |
| Nissan e-NV200 | 40 kWh | 6 kW |
| Mitsubishi Outlander PHEV | 12–20 kWh | 6 kW |
| Mitsubishi i-MiEV | 16 kWh | 6 kW |
Japan and the Netherlands have been the biggest V2G markets with CHAdeMO. In Japan, V2H (vehicle-to-home) is especially popular as earthquake/typhoon backup power. a 62 kWh Leaf can power an average Japanese home for 2–4 days.
CCS has V2G capability in the ISO 15118-20 spec, but production deployments lag far behind CHAdeMO's decade of real-world experience.
Wiring specifications
DC power cable
| Charger rating | DC+ conductor | DC– conductor | Ground |
|---|---|---|---|
| 50 kW (125A) | 25 mm² Cu | 25 mm² Cu | 10 mm² |
| 100 kW (200A) | 50 mm² Cu | 50 mm² Cu | 16 mm² |
| 150 kW+ | 70 mm² Cu | 70 mm² Cu | 25 mm² |
CHAdeMO cables tend to be thicker and stiffer than CCS cables at equivalent power because CHAdeMO never standardized liquid cooling. Passive (air-cooled) cables above 150A get heavy and unwieldy.
Signal wiring (inside the cable)
| Wire | Function | Size |
|---|---|---|
| CAN-H (pin 4) | CAN bus high | 0.5 mm², twisted pair with CAN-L |
| CAN-L (pin 5) | CAN bus low | 0.5 mm², twisted pair with CAN-H |
| Pin 1 (start/stop) | Charger power status | 0.5 mm² |
| Pin 2 (permission) | Vehicle permission | 0.5 mm² |
| Pin 3 (signal GND) | Signal reference | 0.5 mm² |
| Pin 6 (seq. 1) | Connector detection | 0.5 mm² |
| Pin 10 (seq. 2) | Connector detection | 0.5 mm² |
| Shield | EMC shielding | Braid, connected to pin 9 |
The CAN bus pair (pins 4 and 5) must be a twisted pair with characteristic impedance of 120Ω. CAN bus termination resistors (120Ω) are at each end of the bus. one in the charger, one in the vehicle.
Cable length
Standard: 4–5 meters. The weight of an uncooled 50 kW cable is around 3 kg. At 100 kW with 50 mm² conductors, it's 5–6 kg. This is one of the ergonomic complaints about CHAdeMO. the cables are physically difficult for some users.
Electrical characteristics
| Parameter | Value |
|---|---|
| DC voltage range | 50–500V (v1.x) / 50–1000V (v2.0) |
| DC current range | 0–200A (v1.x) / 0–400A (v2.0) |
| Max power | 100 kW (v1.x deployed) / 400 kW (v2.0 spec) |
| CAN bus speed | 250 kbps (v1.x) / 500 kbps (v2.0) |
| CAN bus protocol | CAN 2.0B, extended frames |
| Message rate | 100 ms (10 Hz) |
| Insulation resistance | > 100 Ω/V |
| Contact resistance (DC pins) | < 0.5 mΩ |
| Connector temperature limit | 90°C |
| Insertion cycles | 10,000 minimum (5,000 for some versions) |
| IP rating (mated) | IP44 |
| Operating temperature | –30°C to +50°C |
| Emergency shutdown response | < 100 ms (pin 2 LOW → power off) |
Safety features
CHAdeMO's safety approach is simpler than CCS but effective:
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Hardware interlock (pins 1, 2): independent of CAN communication. Vehicle must assert pin 2 for power and can instantly revoke it. Charger asserts pin 1 only when power is actually flowing. These are galvanically isolated digital signals.
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Connector detection (pins 6, 10): the charger verifies physical connector insertion before starting. Two signals for redundancy.
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Insulation test: same concept as CCS. Charger applies low voltage to DC lines and measures insulation resistance before energizing.
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CAN fault monitoring: the vehicle sends fault flags every 100 ms: battery overvoltage, undervoltage, overcurrent, overtemperature. Any flag → charger stops immediately.
-
CAN communication timeout: if either side stops sending CAN messages for more than 1 second, the other side treats it as a fault and stops.
-
Voltage/current limits: the charger never outputs more voltage or current than the vehicle requested. The vehicle never requests more than its battery can accept. Both sides monitor actual vs. requested values and flag discrepancies.
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Welding detection: after shutdown, charger verifies DC output voltage decays to safe levels. If voltage persists (contactor welded), fault is flagged.
CHAdeMO vs CCS. the full comparison
| Feature | CHAdeMO | CCS (CCS1/CCS2) |
|---|---|---|
| Communication | CAN bus (250/500 kbps) | PLC (10 Mbps) |
| Protocol complexity | Simple (2 CAN messages) | Complex (ISO 15118 stack) |
| Plug & Charge | No | Yes (ISO 15118-2) |
| V2G (bidirectional) | Yes (production since 2012) | Yes (ISO 15118-20, emerging) |
| AC + DC combined inlet | No (separate plugs) | Yes |
| Max power (spec) | 400 kW | 350 kW (CCS) / 900 kW (ChaoJi) |
| Max power (deployed) | 150 kW | 350 kW |
| Connector size | Large (~70 mm Ø) | CCS1: ~70 mm / CCS2: ~90 mm |
| Cable weight (50 kW) | Heavy (no liquid cooling) | Similar (passive) |
| Signal redundancy | Hardware interlock + CAN | PLC only (software) |
| Smart charging | No | Yes (ISO 15118 schedules) |
| Authentication | External (RFID, app) | Embedded (Plug & Charge) |
Where CHAdeMO still lives
Japan
Still the dominant DC standard. Roughly 8,000 CHAdeMO chargers as of 2025. All domestic Japanese EVs supported it. New installations are slowing but existing infrastructure will persist for years.
Legacy installations worldwide
About 25,000 CHAdeMO units outside Japan. Many dual-standard installations have both CCS and CHAdeMO cables. These are gradually being replaced by CCS-only or CCS + NACS as CHAdeMO vehicles age out.
V2G applications
CHAdeMO remains the go-to for V2G deployments, especially in Japan and Europe (Netherlands, UK, France). The decade-long track record and wide vehicle support make it the proven option for bidirectional power.
Compatibility and adapters
- CHAdeMO → CCS: no simple adapter. Different physical connector AND different communication protocol (CAN vs PLC). Protocol conversion boxes exist but are expensive and uncommon.
- CHAdeMO → NACS: Tesla sold a CHAdeMO adapter for their vehicles (~$400) but discontinued it around 2022. Third-party options may exist.
- CHAdeMO → Type 1/Type 2 (AC): not applicable. CHAdeMO is DC only. You need a separate AC connector.
- CCS → CHAdeMO vehicle: adapters extremely rare. The CCS-to-CHAdeMO protocol translation is complex and requires bidirectional CAN/PLC gateway hardware.
Installation notes
- Simpler than CCS at the low-power end. A 50 kW CHAdeMO charger is electrically similar to a 50 kW CCS charger. Same power supply requirements.
- CAN bus wiring is much less sensitive than PLC. CAN is designed for automotive environments with noise, vibration, and temperature extremes. PLC can be fiddly in electrically noisy environments.
- Cable management is more important because CHAdeMO cables are heavier. A retractor or cable management arm helps with ergonomics at public stations.
- Dual-standard stations (CCS + CHAdeMO) usually share a single DC power supply and switch between connector via internal contactors. Only one connector can be active at a time.
- End-of-life planning: if you're deploying new infrastructure today, CHAdeMO is not the right choice unless you're specifically targeting the Japanese market or V2G applications with existing CHAdeMO vehicles.
CHAdeMO earned its place in EV history as the pioneer of DC fast charging. Its CAN-based simplicity, hardware safety interlocks, and working V2G implementation are genuine engineering achievements. The standard lost the market battle to CCS, but the ~50,000 CHAdeMO chargers worldwide won't disappear overnight, and its V2G legacy will influence charging standards for years to come.