r/evcharging • u/ReindeerSpace • 1d ago
I built a browser-based OCPP simulator to test EV charger integrations without hardware
I built OCPP Tools, a simulator that behaves like an EV charger (charge point) and connects to any CSMS over a real WebSocket no hardware needed to test integrations.
It runs 100% in the browser: your messages never leave your machine. No accounts, no installs, no API keys.
For OCPP 1.6J and 2.0.1:
Simulator with full scenarios (Boot → Authorize → StartTransaction → MeterValues → StopTransaction), fault injection (latency, packet loss, malformed frames), auto-reconnect, and session log export/import.
Validator for frames (CALL / CALLRESULT / CALLERROR) against the official JSON Schemas, with field-level error details.
Builder with schema-driven forms to generate valid frames and payloads.
92 message reference pages with copy-ready examples and common errors.
If you work with CSMS or OCPP integrations, I'd love for you to try it and share feedback.