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Serial control for MK2 PV Router

Tags: #<Tag:0x00007f1bd93e9ee0> #<Tag:0x00007f1bd93e9e18>

Hi All,

To start could I humbly suggest that the mods create a “Mk2PVRouter” tag on this forum because I think it would be helpful for people specifically looking for information related to it.

I would like to ask if anyone has had success in using serial communication to control the MK2 instead of the typical CT clamps? I’ve searching a lot but I haven’t found an example of anyone who has used a different form of control except for CT.

In my particular case I use grid tied inverters with limiters so my net export is always zero, If I could interface with the MK2 using serial to sent it a watt value to heat the water by then I could implement some logic that will allow me to better control power balances between my battery, house and time of day and predicted weather.

If anyone could direct me to anyone who has done this in the past I would be really grateful, of if they had suggestions how I could approach the problem to fixing it myself it would be brilliant. Thanks!

Robin has his own website, which is by far the best place to go for support.

Robin will no doubt correct me, but I can’t see any other form of control working efficiently and effectively. The Mk2 router responds within 2 mains cycles to a change in the usage, a serial comms channel is going to delay that reaction considerably, leading to unwanted import or export.

I think the essence of your problem will be that the diverter and battery charger are trying to control each other, and to resolve that you need to decide which takes priority and arrange the positioning of the “grid” c.t’s for each so that each only sees the correct usage that it’s allowed to influence.

Reading between the lines, it seems that you are actually asking for a much less precise control of your water heating load. That would be possible (but you’d need to heavily modify the Mk2 software to accomplish that - it would need to adjust its m/s ratio to achieve the average power that you specify to it) and you’d lose the very precise load balancing that the Mk2 is designed to achieve.