SunSpec model 302 Irradiance Model

SunSpec model 302 is the irradiance information model in the SunSpec standard. It defines a register block that reports solar irradiance readings over Modbus. The block opens with a read-only ID register that holds 302, followed by a length register that holds 5. Five read-only uint16 data points follow, all in W/m2: global horizontal irradiance (GHI), plane-of-array irradiance (POAI), diffuse irradiance (DFI), direct normal irradiance (DNI) and other irradiance (OTI). The RainWise PVmet-500 weather station is SunSpec compliant and supports models 302, 303 and 307. On the PVmet-500, model 302 carries only global horizontal, plane-of-array and other irradiance, so the remaining points should be ignored. The PVmet-500 manual pairs this model with its default Modbus RS-485 communication settings.

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• sentence 1: support check: partial - Passages show 302 is the SunSpec irradiance model with a register block of irradiance values, but Modbus transport is only implied via the PVmet-500's Modbus settings.
• sentence 5: support check: partial - Text says PVmet-500 provides GHI, POA and other irradiance and other data should be ignored, but the manufacturer attribution 'RainWise' etc. aside, 'only' is consistent; the minor gap is that the statement matches closely though 'remaining points' is paraphrase.
• sentence 6: support check: partial - The manual places a Modbus RS-485 default settings table amid the 302 text, but doesn't explicitly pair it with the model; it's likely a layout artifact.
• sentence 1: review: partial - The passages show 302 as the SunSpec solar irradiance model with a register table of irradiance points, but Modbus transport is only hinted at by a nearby RS-485 settings table title. -->