SunSpec Alliance

Device Information Models — SunSpec Modbus · SunSpec JSON · IEEE 1547-2018 / IEEE 2030.5 interoperability

SunSpec defines vendor-neutral information models for inverters, storage, meters, and other DER. The same model can be encoded as Modbus registers (field / installer) or as JSON (MQTT, REST, OpenAMI). IEEE 1547-2018 names SunSpec Modbus and IEEE 2030.5 as the two interoperable communications methods for the same DER functions. The 701–712 series is that shared schema.

What it is at its core

SunSpec is a device information model, not a WAN protocol. Three layers:

• Models — numbered blocks (1 Common, 101–103 legacy inverters, 701–712 DER, 802+ storage, 200-series meters). Each model is a group of points and nested groups.
• Encodings — Modbus RTU/TCP (register map after the SunS marker) or JSON (canonical definition encoding; JSON instances for MQTT/REST).
• Profiles — which models a device must implement. The IEEE 1547-2018 profile requires Model 1 plus 701–712 for the grid-support functions that CSIP then carries over IEEE 2030.5.

How it came to be

The schema that covers IEEE 2030.5 compatibility

Two files matter:

1. schema.json — JSON Schema (draft-07) for how every SunSpec model is written. The standards array on each point is where 1547/2030.5 alignment is declared.
2. Models 1 + 701–712 — the instance definitions that implement every CSIP/IEEE 2030.5 DER grid-support function. Official copies are vendored at sunspec-models/json/ (Apache-2.0, sunspec/models).

IEEE 2030.5 does not get a second SunSpec model set. CSIP maps functions onto 2030.5 resources; the 700-series is the device-side schema for those same functions. Official point tags say IEEE 1547-2018 (behavior). IEEE 2030.5 is the WAN protocol that writes the equivalent DERControl objects.

Device map — Model 1 + 701–712

CSIP Table 9 → SunSpec 700-series

Cited from the SunSpec CSIP Implementation Guide v2.1 (Table 9) plus the official 701–712 JSON group names. Empty CSIP cells mean the function is default-only or not scheduled as a DERControl event.

Model 702 CtrlModes — advertised functions

This bitfield is the SunSpec-side equivalent of IEEE 2030.5 DERCapability.modesSupported. Bits from official model_702.json:

Exact JSON Schema (schema.json)

This is the official SunSpec JSON Schema for model definitions — including the standards field used to mark IEEE 1547-2018 (and therefore IEEE 2030.5-compatible) points. Source: sunspec/models json/schema.json.

sunspec-models/json/schema.json — Apache-2.0 copy of sunspec/models

Loading schema.json…

What schema.json requires

Curve-group shape (Models 705–710, 712)

IEEE 2030.5 DERCurve resources are this nested group, not a flat register list. Official Model 705 skeleton:

{
  "id": 705,
  "group": {
    "name": "DERVoltVar",
    "label": "DER Volt-Var",
    "type": "group",
    "points": [
      { "name": "ID", "value": 705, "type": "uint16", "mandatory": "M", "standards": ["IEEE 1547-2018"] },
      { "name": "L", "type": "uint16", "mandatory": "M", "standards": ["IEEE 1547-2018"] },
      { "name": "Ena", "type": "enum16", "access": "RW", "standards": ["IEEE 1547-2018"] },
      { "name": "AdptCrvReq", "type": "uint16", "access": "RW", "standards": ["IEEE 1547-2018"] },
      { "name": "NPt", "type": "uint16", "standards": ["IEEE 1547-2018"] },
      { "name": "NCrv", "type": "uint16", "standards": ["IEEE 1547-2018"] }
    ],
    "groups": [
      {
        "name": "Crv",
        "count": "NCrv",
        "type": "group",
        "points": [
          { "name": "ActPt", "type": "uint16", "access": "RW", "standards": ["IEEE 1547-2018"] },
          { "name": "DeptRef", "type": "enum16", "access": "RW", "standards": ["IEEE 1547-2018"] }
        ],
        "groups": [
          {
            "name": "Pt",
            "count": "NPt",
            "type": "group",
            "points": [
              { "name": "V", "type": "uint16", "units": "VNomPct", "access": "RW", "standards": ["IEEE 1547-2018"] },
              { "name": "Var", "type": "int16", "units": "DeptRef", "access": "RW", "standards": ["IEEE 1547-2018"] }
            ]
          }
        ]
      }
    ]
  }
}

Use the file picker above for the full official model_705.json (symbols, scale factors, reversion timers). Ride-through models 707–710 nest three curves per stored set: MustTrip, MayTrip, MomCess — the three IEEE 2030.5 LVRT/HVRT/LFRT/HFRT mode families.

Relationship to other standards

Standard	Relationship to SunSpec
IEEE 1547-2018	Defines DER behavior. Annex E names SunSpec Modbus as one of two interoperable interfaces. 701–712 points tagged IEEE 1547-2018 are that interface.
IEEE 2030.5	WAN application protocol (HTTPS/XML, TLS, certs). DER function set is based on the SunSpec inverter control model. CSIP is the SunSpec profile of 2030.5.
CSIP	Which 2030.5 function sets are mandatory (Rule 21). Table 9 is the control mapping; 701–712 are the device schema behind it.
Modbus RTU/TCP	Transport for the register encoding. RS-485 carries the map; SunSpec is the map.
TLS 1.2	Required for IEEE 2030.5. Not required for local SunSpec Modbus on an isolated RS-485 bus (Phase 1–2).
OpenAMI MQTT	Village northbound. Payloads align to SunSpec JSON group/point names so a later 2030.5 gateway has a known model to wrap — not a second register language.

Relevance to village microgrids

Key takeaways

• SunSpec is the device schema; IEEE 2030.5 is one encoding + session of that schema for utilities.
• The IEEE 2030.5-compatible set is Model 1 + Models 701–712, not the whole SunSpec catalog (101–103, 200-series meters, 802 batteries are adjacent).
• Look at each point’s standards: ["IEEE 1547-2018"] array — that is the documented 1547/2030.5 subset. Empty means optional / SunSpec-only.
• Canonical files: sunspec-models/json/schema.json and model_701.json…model_712.json.
• For ISV: Phase 1–2 speak SunSpec JSON/Modbus; Phase 3 wraps the same points in 2030.5 CSIP.

Further reading

• sunspec/models (SMDX + JSON) ↗ — Apache-2.0 source of the files on this page
• SunSpec Modbus specifications ↗ — Device IM, DER IM, IEEE 1547-2018 profile
• CSIP implementation guide ↗
• 700-series DER models (701–712) ↗
• IEEE 2030.5 deep-dive · IEEE 1547 deep-dive