Connector Availability and Status relationship

[SiarheiVolkau]

I'm writing this to make things clear, it might/might not reflect real issue in the codebase.

As I know availability is designed to be persistent connector attribute, controlled remotely via ChangeAvailability.
While connector status shall reflect actual status of the physical connector - it is a function of real status and availability and it don't have to be persistent.

So the question is: why open-ocpp stores status in the database and don't store availability anyhow.
I guess, its because availability takes precedence and Status::Unavailable strictly bidirectionally equal to Availability::Inoperative, only in that case it makes sense. Another drawback of that approach is that real connector status can't be Unavailable because it overrides availability too.

Are my assumptions correct?

[c-jimenez]

Hi,

The availability status is not a well-defined status in OCPP 1.6.
The standard says :

Central System can request a Charge Point to change its availability. A Charge Point is considered available
(“operative”) when it is charging or ready for charging. A Charge Point is considered unavailable when it does not
allow any charging.

So in my implementation I decided to merge what you call the availability with the Unavailable status of a connector when the Central System ask the connector to be in Inoperative state. All the other connector statuses are then reflecting the Operative state.

I didn't think it would be a drawback since normally in Inoperative state the connector cannot allow any charge and thus cannot be on any other state than Available or Unavailable.

Is this a blocking point for your Charge Point implementation?
If so, which are your use cases which needs to separate this 2 information?

[SiarheiVolkau]

Is this a blocking point for your Charge Point implementation?
If so, which are your use cases which needs to separate this 2 information?

Yes, it is. Let me describe the situation.
I have a ChargePoint-like device (CP) and up to 4 Connector-like devices (CNs) connected via LAN.
CP can control power supply of CNs, so there's a period for CN to boot up (usually 2 minutes).
For that period of time it will be good to use Unavailable status, since it fit best.
Also, IMHO, it shall remain Unavailable if it didn't appear in 2 minutes (physically absent).
That's where the things go wrong.

[c-jimenez]

You can control the status of your connectors and force it to stay 'Unavailable' until they are ready by using the IChargePoint::statusNotification().

Is this not sufficient?

[SiarheiVolkau]

I do that, although I also want to know Availability which is set by CentralSystem for whatever reason.
e.g. CS admin might set connector to Inoperative for planning maintenance.
So in my opinion Status and Availability shall be independent things.

Thank you for the quick answering, now I realized what I have to do.