# Edge EV Charger controller Part number: EVSE-C-3x32A Status: Shipped Price: € 125 excl. VAT (per unit excl. VAT, ask for a quote above 5 units) CE declaration: https://mycharger.edgetech.nl/CE_ChargerController.pdf Canonical: https://edgetech.eu/electronics/evse-c-3x32a Updated: 2026-10-13 AC charge controller board for one Mode 3 charge point, up to 3×32 A (22 kW), with integrated relay drive, per-phase current and voltage metering, and Modbus RTU control. The board inside most EdgeTech-based chargers since 2021. ## Specifications | Specification | Value | |---|---| | Charging | IEC 61851-1 Mode 3, 1-phase or 3-phase, 6–32 A continuous, max 3×32 A (22 kW) | | Advertised maximum | 16 A without jumper, 32 A with jumper; remotely limited per second over Modbus (register 0x0201) | | Microcontroller | 8-bit microcontroller, 16 MHz, bare-metal C firmware (open source) | | Metering | On-board per-phase current and voltage measurement, session and lifetime energy in 1/256 kWh steps. Not MID certified. | | Switching | Integrated relay drive for the charge contactor; stuck-relay detection; earth, neutral and L1 self-test at every boot | | Fieldbus | Modbus RTU slave over RS485, 9600 8N1 (19200 with EVSE-SC-02), factory address 1 (answers only after a state change) | | Bus cable | 3 × 0.75 mm² multi-core (stranded). No solid-core cable and no raw Ethernet cable in the terminals; Ethernet only with RJ45 connectors (adapter board on request) | | Failsafe | No Modbus message for 2 s → safe mode; internal temperature 62 °C → limit to 10 A, higher → charging off | | DC leakage protection | 6 mA DC-to-PE sensor (EVSE-X-DCD, IEC 62955) included with every controller; trip reported as error bit 5 (value 32) | | Cable and lock | Fixed cable or Type 2 socket; PP resistor read for cable rating; lock port for the EVSE-X-CL cable lock driver, with lock/unlock feedback | | Signalling | Onboard RGB LED or addressable LED strip (36 LEDs); CP disconnect for EV wake-up per IEC 61851-23 Ed. 2 | | Supply | 90–300 V AC, 50 Hz, 3 W | | Dimensions | 168 × 122 × 25 mm | | Enclosure rating | IP00 (bare board, for installation in an enclosure), Class I | | CE | Declaration 2022-001 EVSE-C-01: LVD 2014/35/EU, EMC 2014/30/EU, RoHS 2011/65/EU. Updated declaration to EN IEC 61851-1:2019 and EN IEC 61851-21-2:2021 soon | | Made in | Europe | Interfaces: Modbus RTU RS485, RGB LED / addressable LED strip, cable lock, CP disconnect, SPI ISP for firmware Standards: IEC 61851-1, IEC 61851-23 Ed. 2 (wake-up), IEC 62955 (with EVSE-X-DCD), Modbus RTU ## What it is One board, one charge point. The EVSE-C-3x32A talks to the car over the control pilot, drives the contactor, measures current and voltage on each phase, and reports everything over Modbus RTU. Put it in an enclosure with a contactor, an MCB, an RCD and (for DC leakage) the EVSE-X-DCD module, and you have a Mode 3 AC charger. It runs on its own, at a static limit of 16 A or 32 A. Connected to a site controller it becomes a dynamically limited charge point: the controller writes a new current limit every second, and the board falls back to a safe state if those writes stop. ## What is on the board - Control pilot generation and measurement (states A, B, C, D per IEC 61851-1), proximity pilot reading for cable rating. - Relay drive for a 3-phase contactor, with stuck-relay detection and a boot-time self-test on earth, neutral and L1. - On-board per-phase current and voltage measurement, giving session energy, lifetime energy and per-phase session energy. - RS485 transceiver, Modbus RTU slave. - Lock port for socket variants: the [cable lock driver EVSE-X-CL](/electronics/evse-x-cl) drives the socket lock and reports its position. - CP disconnect output. Used to wake cars that go into deep sleep after a long pause, per IEC 61851-23 Edition 2. Shipped in firmware 2.10.17. - Temperature sensor. Above 62 °C the board limits to 10 A; above that it stops. - LED output: the onboard RGB LED, or an addressable LED strip of up to 36 LEDs. - SPI header. The site controller can reflash the board's firmware in the field. ## Integration notes - The controller must answer Modbus requests within 40 ms. Modbus over Ethernet (a TCP gateway) works in principle, but answers too slowly for EdgeTech site controllers; wireless Modbus does not work. Use a bus topology with 3 × 0.75 mm² multi-core (stranded) cable. No solid-core cable and no raw Ethernet cable in the terminals; Ethernet cable only with RJ45 connectors fitted (adapter board with RJ45 socket on request). See [installation](/docs/installation#rs485-bus). - The charger leaves the factory at Modbus address 1. Address 1 is special: after boot the charger does not answer there, only after a state change. A site controller moves each new charger to its own address, so all chargers can be reached; with your own controller, write an address of 2 or higher to register 0x0200 after a state change. - All analog registers are in 1/256 units: 5632 in a current register means 22.0 A. - A 1-phase to 3-phase switch during a session upsets most cars. Stop the session, wait 10 s, switch, restart. The protocol is open and documented: [Modbus registers](/docs/modbus-registers). Load-balancing behaviour: [Load balancing](/docs/load-balancing). ## Buying € 125 per board excl. VAT and shipping. Above 5 units, ask for a quote. Volume customers get the board on a reel-to-enclosure basis with their own firmware defaults (address, LED type, lock type, 1P/3P) preloaded. [Contact us](/contact). ## Installation ![Wiring diagram: power cable L1 L2 L3 N PE to the charge controller, switched L1 L2 L3 N through the RDC-DD ring into the Type 2 charge cable with PE and control pilot, and the Modbus cable to the site controller.](https://edgetech.eu/img/install/charger.svg) Charge controller: power cable from a charger group (Type A RCD + 3-pole + N breaker) to POWER IN; POWER OUT through the RDC-DD into the charge cable; PE straight to the charge cable; Modbus to the site controller. Rules: https://edgetech.eu/docs/installation#charge-controller ## CAD and drawings - 3D model (STEP): https://edgetech.eu/cad/evse-c-3x32a.step - Drawing (PDF, A3): https://edgetech.eu/cad/evse-c-3x32a.pdf - Drawing (SVG): https://edgetech.eu/cad/evse-c-3x32a.svg For fit and installation only, not for manufacture. Outline, mounting holes, connector positions and component height envelopes; dimensions marked ≈ are estimated. ## Questions **Can I control the charge current from my own controller?** Yes. Write the maximum current in amps to Modbus register 0x0201 at least once per second. Writing 0 stops charging. If the board receives nothing for 2 s it falls back to its static limit. **Is the built-in meter MID certified?** No. The metering is accurate enough for load balancing and consumption overviews, but it is not a legal billing meter. Add an external MID meter if you bill by kWh. **Does it support ISO 15118 or Plug & Charge?** Not today. The board does basic PWM signalling per IEC 61851-1. ISO 15118 is on the roadmap as an add-on module; see the standards page. **Is the firmware open?** Yes. Firmware, register list, 3D brackets and the wiring diagram are on GitHub at edge-tech-eu/SmartEVSE.