victron-cerbo-modbus-device-onboarding

victron-cerbo-modbus-device-onboarding is a skill for Claude Code from Ed3Design/ed3design-engineering-bundles. It costs 161 tokens per session (1,494 once invoked), scanned A, original, MIT.

A procedure for adding a Modbus-TCP device—a network device that exchanges data using the Modbus protocol—to a Victron Cerbo GX energy-management system.

In plain words
What is it for?
Use it to diagnose and enable EV chargers, energy meters, inverters, and other supported Modbus-TCP devices on the Cerbo network.
Why use it?
It addresses cases where a reachable device still does not appear in the Cerbo interface or its internal data system.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin. Also seen: mentions subagents.

Part of the embedded-systems plugin — 1 skill shipped together

Good fit Use it to diagnose and enable EV chargers, energy meters, inverters, and other supported Modbus-TCP devices on the Cerbo network.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/ed3design/ed3design-engineering-bundles/victron-cerbo-modbus-device-onboarding
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add Ed3Design/ed3design-engineering-bundles --skill victron-cerbo-modbus-device-onboarding
Clone the repo
git clone --depth 1 https://github.com/Ed3Design/ed3design-engineering-bundles

Made for: Claude Code.

Or install embedded-systems, the plugin that ships this one along with the rest of its 1 skill.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for victron-cerbo-modbus-device-onboarding

README.md
[![agentmods](https://agentmods.dev/badge/skills/ed3design/ed3design-engineering-bundles/victron-cerbo-modbus-device-onboarding/github.svg)](https://agentmods.dev/skills/ed3design/ed3design-engineering-bundles/victron-cerbo-modbus-device-onboarding)
Your own site
<a href="https://agentmods.dev/skills/ed3design/ed3design-engineering-bundles/victron-cerbo-modbus-device-onboarding"><img src="https://agentmods.dev/badge/skills/ed3design/ed3design-engineering-bundles/victron-cerbo-modbus-device-onboarding/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for victron-cerbo-modbus-device-onboarding

Your own site · 80×15
<a href="https://agentmods.dev/skills/ed3design/ed3design-engineering-bundles/victron-cerbo-modbus-device-onboarding"><img src="https://agentmods.dev/badge/skills/ed3design/ed3design-engineering-bundles/victron-cerbo-modbus-device-onboarding.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 161 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,494 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00161 $0.01494
Opus 5 $0.00081 $0.00747
Sonnet 5 $0.00032 $0.00299
Haiku 4.5 $0.00016 $0.00149

Measured 12d ago against content hash 1e5284327ac7, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

victron-cerbo-modbus-device-onboarding scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 12d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

embedded-systems/skills/victron-cerbo-modbus-device-onboarding/SKILL.md · 112 lines

How it starts

The opening of the file, as written. The whole thing — 112 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Victron Cerbo GX — Onboarding a new Modbus-TCP device

Pattern verified against a real Cerbo GX with a JK-BMS that remained invisible at the Modbus layer despite correct VLAN routing. The non-obvious cause is the per-port Enabled=0 factory-default. The 5-step sequence + dbus-send fix is the deterministic onboarding workflow; the fallback branch covers Enabled=1 cases where the device is still invisible.

The non-obvious problem

dbus-modbus-client discovers new Modbus devices via TCP subnet scan (port 502, every 25 s) — creates settings in localsettings and sets Enabled = 0 as the default. The device is registered but invisible. No hint in the log, no error in the UI.

Applies to all Victron Modbus-TCP devices: EV Charging Station, Carlo Gavazzi meters, SolarEdge, external inverters.

Diagnostic sequence (5 steps)

SSH access pattern (replace placeholders with your own credentials and hosts):

ssh -J <your-jumphost-user>@<your-jumphost-ip> root@<cerbo-ip>

Note: the Cerbo's root SSH access is enabled via the Cerbo UI under Settings → General → Access Level → Superuser. Use ssh-copy-id to set up key-auth and avoid password prompts. Do NOT hardcode passwords into shell scripts or skill bodies.

1 — Network check

ping -c 2 <device-ip>

No response → LAN/VLAN problem, check DHCP. Response → continue.

2 — D-Bus check

dbus -y | grep -i "evcharger\|evc_\|<device-type>"

Empty → settings problem (Enabled=0 candidate). Service visible → check UI refresh / VRM cache.

3 — Read the modbus-client log

cat /var/log/dbus-modbus-client/current | tr -d "\000" | grep -v "^$" | tail -30

Watch for these patterns:

  • Found EV charger: Victron Energy AC22NS → device detected ✓
  • Setting /Settings/Devices/<id>/Enabled does not exist yet → default-Enabled problem

4 — Check the Enabled value

dbus -y com.victronenergy.settings /Settings/Devices/<device-id>/Enabled GetValue

Returns 0 → that's the bug. Device-ID from log (format: evc_<Serial>).

Read the full file on GitHub · 112 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 12d ago First seen · 112 lines · 161 tokens per session scan A 1e5284327ac7

Subscribe to this mod's changes

victron-cerbo-modbus-device-onboarding is a skill published in the GitHub repository Ed3Design/ed3design-engineering-bundles (2 stars, last pushed 1mo ago), licensed MIT. It adds 161 tokens to every session and 1,494 once invoked, about $0.0008 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Related

Other skills, from other repositories

ros2-microros

Skill "ros2-microros" from Leehyunbin0131/claude-ros2-skills, covering micro-ros instructions (ubuntu 24.04 lts & ros 2 jazzy), 1. architecture, 2. documentation entry points, 3. key concepts & patterns and a. embedded client node setup (rclc in c).

Leehyunbin0131/claude-ros2-skills · 29 tokens

nurb

Design 3D-printable parts as Python functions with nurb. Use when the user wants a part designed, changed, or checked for 3D printing (a bracket, mount, holder, enclosure, shelf, or any STL/STEP to print), and in any directory with a parts/ folder. The user describes the part and judges it in a browser; you model it.

Shpigford/nurb · 81 tokens

esp32-expert

This skill should be used for ESP32-specific hardware and runtime work in ESP-IDF, Arduino-ESP32, or PlatformIO projects: target/build detection, FreeRTOS tasks and ISRs, memory/DMA, peripherals, power, networking/security, OTA, crash diagnosis, and unattended reliability. Trigger on "debug this ESP32 crash", "review…

johnkozaris/jko-claude-plugins · 137 tokens

esp32-expert

This skill should be used when the user is writing, reviewing, debugging, or architecting C++ firmware for ESP32 and variants (ESP32-S2, S3, C3, C6, H2, P4) using ESP-IDF or PlatformIO. Provides expert critique covering FreeRTOS task design, memory management (IRAM/DRAM/PSRAM), peripheral drivers (I2C/SPI/UART/GPIO)…

mathisk2095/jko-claude-plugins · 193 tokens

continuum-fea

Run the continuum (tier-3) FEA on a part a beam model can't capture — bracket, fitting, lug, hull bottom panel, pressure shell, sponson root — with gmsh + CalculiX (ccx). Use when an audit's analytic check or the in-house beam FEA is too coarse and you need a real 3-D stress/displacement or buckling field. Drives the…

JMMonte/agentic-digital-twin · 136 tokens

add-scored-audit

Add a new executable scored check (PASS/WARN/FAIL) for a requirement to a hardware-as-code project's audit harness. Use when a requirement, clearance, mass budget, margin, or anchor needs to be verified automatically. Enforces the rules: read the build's exported JSON artifacts, never duplicate a geometry constant…

JMMonte/agentic-digital-twin · 88 tokens