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ottopaulsen / node-red-contrib-power-saver

A Node-RED node to saver money by turning off when the power is most expensive
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Water heater turned off for a complete hour when schedule was on #128

Open shadowano opened 1 year ago

shadowano commented 1 year ago

I'm using the following to control my water heater (VVB): Save money using Lowest price and Best Save with schedule merger: strøm node-red save money

Followed the setup from https://powersaver.no/examples/example-grid-tariff-capacity-part.html#introduction

Calculate values strøm node-red calculate values

Reduction and Reset action nodes strøm node-red grid tariff reduction nodes

After seeing the screenshot below where according to the plan from powersaver nodes the heater should be on but the power usage was very low, while hours before and after are higher due to water heater using power. strøm plan

I checked the power consumption for the water heater where it shows no power being used for the whole hour of 01:00-02:00 in the night strøm varmtvannstanken forbruk

I checked the log where all actions from the reduction and reset action nodes end up, and it shows that Reduction Action node turned off the water heater at 00:27:21 and Reset Action node turned it back on at 02:00 (note screenshot shows UTC, while all other times are in GMT+1 (Norwegian winter time) strøm reduction nodes

I checked if the switch was on or off, just to be sure, and the switch was off in the same period: strøm switch varmtvannstanken

What could cause the Reset action to not enable the water heater at 01:00, also when the whole hour uses way lower power than it could. I have set the Reset action node to reset after 300seconds, default value from powersaver.no. I have configured the SAFE_ZONE and BUFFER in Calculate values node with 1 and and 0.5 (or lower, as I have changed the values a bit lower to use more power during an hour). My water heater uses 3kWh, and first grid tariff step is 5kWh. ALARM level is set to 3.

Is there anything else I should be looking at?

ottopaulsen commented 1 year ago

Nice setup you have here, and good explanation. I am not sure what could have happened, but I suspect the grid capacity code has something to do with it. Looks like it did not reduce when it should have. Maybe the consumption value is wrong, for example that the consumption sensor gives value in W while it is expected in kW.

Have you found out anything else yourself?

shadowano commented 1 year ago

I haven't found out why this happened, and it looks like it hasn't happened again. I know my smart device on VVB has a overheating sensor, and it turns off if it's overheating. I don't have logs going that far back for this sensor, so couldn't check it. This doesn't either way explain why the Reset action node did not get called.

My consumption sensors Current Day used and Current Hour used are in kWh, while Active Import is in W.

The setup works great except for this specific issue. It turns off and on the water heater to keep below 5 kWh every day. So I don't think there is anything wrong with what I send as input.