MQTT topics

Everything is published under MQTT.ParentTopic (default rPDU2MQTT).

Paths page: the MQTT topic, Prometheus metric and EmonCMS key for each measurement

Sources › Paths lists the topic for every measurement, with overrides applied.

Bridge

Topic	Payload
`<parent>/Status`	`online` / `offline`. The Last-Will topic, used as every entity's availability topic while `MQTT.LastWill` is on.
`<parent>/rediscover`	Command topic of the bridge's Rediscover button in Home Assistant.
`<parent>/restart`	Command topic of the bridge's Restart button in Home Assistant.

PDU devices

A single PDU instance publishes without a namespace. With several, each has its own namespace (Vertiv rPDU).

Topic	Example payload
`<parent>/<serial>/state`	`normal`
`<parent>/<serial>/alarm`, `…/alarm_attributes`	device alarm state, and its attributes as JSON
`<parent>/<serial>/entity/<entity>/measurements/<type>`	`1082` (e.g. `entity/total0/measurements/apparentPower`)
`<parent>/<serial>/outlets/<n>/measurements/<type>`	`201`
`<parent>/<serial>/outlets/<n>/measurements/<type>/alarm`	`normal`
`<parent>/<serial>/outlets/<n>/state`	`on` / `off`
`<parent>/<serial>/outlets/<n>/name`	`TrueNAS`
`<parent>/<serial>/outlets/<n>/onDelay`, `offDelay`, `rebootDelay`	seconds
`<parent>/<serial>/outlets/<n>/poaAction`	`on`, `off` or `last`

<n> is the outlet's 0-based index in the PDU's data. Measurement types seen on outlets are realPower, apparentPower, current, voltage, powerFactor and energy.

Outlet commands

With ActionsEnabled: true and PDU credentials:

Topic	Entity
`…/outlets/<n>/set`	Switch (`on` / `off`)
`…/outlets/<n>/reboot`	Reboot button
`…/outlets/<n>/resetStats`	Reset Statistics button
`…/outlets/<n>/onDelay/set`, `offDelay/set`, `rebootDelay/set`	Delay numbers
`…/outlets/<n>/poaAction/set`	Power-On Action select

Energy-flow tiers

With EnergyFlow.MqttExport: true, every tier is published as JSON to EnergyFlow.MqttTopicTemplate (default {parent}/energyflow/{id}). Tiers include rooms, floors and sites (location_<id>), PDUs (pdu_<device>), outlets (outlet_<device>_<n>), groups and breakers.

rPDU2MQTT/energyflow/solar:

{"id":"solar","value":5503.66,"power":5503.66,"energy":19334.79,"energy_out":null,"energy_in":null,
 "energy_d":57.16,"soc":null,"units":"W","energyUnits":"kWh","label":"Solar Array","kind":"solar",
 "parents":[],"timestamp":"2026-09-29T13:18:23.414Z"}

Field	Meaning
`value`, `power`	power in `units`
`energy`	lifetime energy counter, in `energyUnits`
`energy_in`, `energy_out`	per-direction energy, for nodes with a directional energy source
`energy_d`	energy since the period boundary (see Totals and counters)
`soc`	state of charge, for nodes with a `soc` source
`timestamp`	time of the reading; for a rolled-up tier, the oldest contributing reading

Unknown values are null.

Home Assistant discovery

Device-based payloads under HomeAssistant.DiscoveryTopic:

<discovery>/device/rPDU2MQTT/config — the bridge.
<discovery>/device/rPDU2MQTT_<serial>/config — each PDU device.
<discovery>/device/rPDU2MQTT_<serial>_outlets_<n>/config — each outlet.
<discovery>/device/energyflow_<id>/config — each exported energy-flow tier.