Schrack i-CHARGE CION
The Schrack i-CHARGE CION and Pro Charger are Mode 3 AC EV charging wallboxes for residential and semi-public installations. This Modbus RTU template connects via RS-485 and gives your ModbusCloud Gateway access to the CP signal state, charging authorisation status, and the current setpoint write register. You can read whether a vehicle is present or actively charging, remotely enable or disable the charge point, and adjust the maximum charging current, making dynamic load management and solar surplus charging straightforward to implement.
- Protocol
- Modbus RTU
- Connection
- RS485
- Registers
- 4, read and write
- Brand
- Schrack
- Compatible models
- i-CHARGE CION · Pro Charger
- Last updated
Registers (4)
2 read, 2 write
| Name | Unit | Access | Address (Hidden until you enter your email) | Function (hidden) | Type (hidden) |
|---|---|---|---|---|---|
| status | Read | ||||
| enabled | Read | ||||
| enable | Write | ||||
| maxcurrent | A | Write |
Loading registers…
Send your device list
If a device is not in the library yet, we build the template for free as soon as we have the register data.
Use cases
- Monitor the CP signal state to verify whether a vehicle is connected and actively charging at any given time.
- Track charging authorisation state across multiple wallboxes to audit who enabled each session and when.
- Write a current setpoint during solar surplus periods to align EV charging with available PV output.
- Alert on unexpected transitions in CP status, such as a drop from state C to state A mid-session, to catch cable or vehicle faults.
- Compare authorisation state against session schedules to verify that off-hours charging restrictions are being enforced.
Installation
Set DIP switches 1 and 2 on the CION charge controller board to the OFF position to activate the RS-485 terminals before making any wiring connections.
Connect the charge controller's A and B RS-485 terminals to the corresponding terminals on the ModbusCloud Gateway using shielded twisted-pair or CAT5 cable; note the manufacturer states shielding earthing is not required for data transfer.
In the ModbusCloud portal, add a new Gateway, import the Schrack i-CHARGE CION template, and assign the correct Modbus unit ID (slave ID), which can be verified or changed via register 500 on the device.
Trigger a test read of register 139 in the portal's live register view and confirm the returned ASCII value matches the current CP state visible on the wallbox LED, for example 0x41 for standby state A.
Things to watch for
Register 139 returns a numeric value, not a letter. What does it mean?
Register 139 holds the CP signal state as a 16-bit ASCII-encoded character. The raw integer 65 (0x41) means state A (standby), 66 means B (vehicle detected), 67 means C (charging). If your portal displays the raw integer, divide by the ASCII table to read the letter, or apply the character conversion in your dashboard formula.
I wrote 1 to register 100 but charging did not start. Why?
Charging authorisation via register 100 only takes effect when the charger is in a valid state: a vehicle must be connected (CP state B or C) and no cable or configuration error may be active. If register 100 cannot be applied, the charger sets an internal authorisation-ignored flag. Resolve any underlying fault first, then re-write the enable register.
The gateway connects but all register reads return timeout errors. What now?
Confirm DIP switches 1 and 2 are both set to OFF on the charge controller board; if either is ON the RS-485 bus is not active. Also verify the unit ID in the portal matches the slave ID configured on the device, and check that no other RS-485 master is simultaneously polling the same bus.
Is it safe to write any value to the current setpoint register during an active session?
Write register 101 with care. The charger accepts values in the range supported by its configuration; writing a value outside that range or reducing current abruptly during an active session may cause the vehicle to pause charging or log a session error. Always ramp current changes gradually and validate that the written value is within the cable's rated current before writing.
More Schrack templates
Want to see how it works?
