Add more DVG4013 features

[andig]

The documentation seems to indicate that this meter supports more registers than currently implemented. It would be great to add those.

I would appreciate if anybody with a corresponding meter would get in contact.

[ionfan]

i have this meter and i am very interested in improvements regarding more support for the DVG4013.
Especially the current wattage would be intersting to view.
What information do you need? I attached a screenshot from the vendor-software so that you can see which values can be read.

[andig]

Ouch, seems they are defined in https://github.com/gonium/gosdm630/blob/master/meters/impl/dzg.go#L24 but not used. Will add asap.

[frankrichter]

https://github.com/gonium/gosdm630/blob/master/meters/impl/dzg.go#L25 isn't correct: 0x000 is Import (active) power and 0x0002 is Export (active) power. All DZG meter readings are unsigned integers (uint32). To get a signed power reading you have to calculate Import - Export.

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[andig]

0x000 is Import (active) power and 0x0002 is Export (active) power.

Right. This was never tested before, implementation was done blindly.

@ionfan would it be possible to get remote access to your meter, e.g. using ssh or vpn, for testing? Please pm me at [email protected].