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SunSpec Model Definitions
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Model 701 InvSt - Shouldn't it have a "RUNNING" state? #218

Closed jsbosch closed 3 years ago

jsbosch commented 3 years ago

When the inverter is on (St == ON), shouldn't InvSt reflect the status of the inverter under normal operating conditions? Seems we need an additional state such as RUNNING or OPERATING. STANDBY seems redundant with SLEEPING, so can we perhaps repurpose that slot?

bobfox commented 3 years ago

Historically, the MPPT state has been intended to be the normal running state but this PV centric. I think we should change MPPT to RUNNING. Any comments?

jsbosch commented 3 years ago

I agree with the change.

FW22 commented 3 years ago

I also agree... but isnt it too late for a breaking change? The standard is published and industry is already implementing Off, Sleeping, Starting, MPPT, Throttled, ShuttingDown, Fault, Standby. If you change MPPT to Running, you should make very clear that for PV inverters, this means MPPT and that they should indicate Throttled if the are running curtailed by some external or internal power limit.

jsbosch commented 3 years ago

I don't believe this is a breaking change. The label is not sent as a value, so implementations can really call it whatever they want.

bobfox commented 3 years ago

I agree, it is not a breaking change at the Modbus level. It is a breaking change at the model definition level. We have discussed internally and will bring it to the workgroup next week for a decision. I recommend we make the correction. This one seems particularly important to fully support storage inverters. I also think MPPT was just a poor choice to begin with.

FW22 commented 3 years ago

If you are going to have a discussion on this, please consider the other states as well: The THROTTLED state is also PV specific and does not apply to battery inverters. SLEEPING sounds like what the PV inverter does at night. STANDBY should be sufficient... or it has to be clarified what the difference is.

bobfox commented 3 years ago

The MPPT enumeration will be changed to RUNNING. The other enumerations remain the same as there is little support for additional changes.