{"id":27973,"date":"2024-02-23T09:53:18","date_gmt":"2024-02-23T07:53:18","guid":{"rendered":"https:\/\/www.victronenergy.com\/blog\/?p=27973"},"modified":"2024-02-23T10:35:49","modified_gmt":"2024-02-23T08:35:49","slug":"node-red-update-for-victron-users","status":"publish","type":"post","link":"https:\/\/www.victronenergy.com\/blog\/2024\/02\/23\/node-red-update-for-victron-users\/","title":{"rendered":"Node-RED – update for Victron users"},"content":{"rendered":"

In this blog Dirk-Jan Faber<\/em> shows us some of the new tools which have been made available in the latest version changes to Node RED, and where to find the latest files.<\/p>\n

Between releases 3.14 to 3.20 quite a lot has changed on the Node-RED nodes, but not all of the changes are immediately obvious when you check your Node-RED flows. In this blog post I\u2019ll walk you through the changes that will help you to create more efficient and easy-to-use flows.<\/span>\u00a0<\/span><\/p>\n

If you are not already familiar with Node-RED, you can read all about it here<\/a>.<\/span><\/p>\n

Nodes <\/span>showing<\/span> the<\/span> last <\/span>seen<\/span> value<\/span><\/span><\/h4>\n

Previously<\/span>,<\/span> the<\/span> input <\/span>nodes<\/span> reported<\/span> \u201c<\/span>O<\/span>k\u201d or \u201c(<\/span>D<\/span>is)<\/span>C<\/span>onnected<\/span>\u201d as a status. With<\/span> the<\/span> update to<\/span> 3.20 this<\/span> behavio<\/span>u<\/span>r<\/span> has changed<\/span> \u2013 it<\/span> now<\/span> reports<\/span> the<\/span> last value<\/span> seen<\/span> by<\/span> the<\/span> node. This is how the input node used to appear:<\/span><\/span><\/p>\n

\"\"<\/div><\/a><\/p>\n

It now appears like this, for example:<\/p>\n

\"\"<\/a><\/p>\n

\u00a0<\/span>Having<\/span> your<\/span> flow open <\/span>and<\/span> being<\/span> able<\/span> to<\/span> view<\/span> the<\/span> PV power<\/span><\/span> value<\/span> <\/span>change <\/span><\/span>makes<\/span> developing<\/span> the<\/span> rest of <\/span>the<\/span> flow a lot <\/span>easier<\/span>. <\/span>If<\/span> you<\/span> expect<\/span> to<\/span> see<\/span> values<\/span> in<\/span> kilowatts <\/span>but <\/span>you<\/span> see<\/span> the<\/span> values<\/span> in watts<\/span>, <\/span>you<\/span>\u2019ll<\/span> need<\/span> to<\/span> divide<\/span> by<\/span> 1000 <\/span>t<\/span>o<\/span> obtain<\/span> the<\/span> expected<\/span> value<\/span>s<\/span>.<\/span><\/span><\/p>\n

\"\"<\/div><\/a><\/p>\n

If<\/span> you<\/span> don\u2019t<\/span> like <\/span>this<\/span> new<\/span> behavior<\/span>, <\/span>you<\/span> can<\/span> disable<\/span> it<\/span> via <\/span>the<\/span> <\/span>Configuration<\/span> nodes<\/span><\/span>, <\/span>and<\/span> then<\/span> select <\/span>the<\/span> <\/span>Victron<\/span> Energy Client<\/span><\/span>. <\/span>Previously<\/span> this<\/span> configuration<\/span> node <\/span>offered<\/span> no <\/span>\u2018<\/span>options<\/span>\u2019 –<\/span> now<\/span> there<\/span> are <\/span>two<\/span> checkboxes<\/span>. The first <\/span>one<\/span> allows<\/span> you<\/span> to<\/span> disable<\/span> the<\/span> \u2018<\/span>value<\/span>\u2019 readings<\/span> and<\/span> revert<\/span> simply<\/span> to<\/span> showing<\/span> \u201c<\/span>connected<\/span>\u201d. <\/span>You<\/span> probably<\/span> want <\/span>to<\/span> leave<\/span> the<\/span> option <\/span>checked<\/span>.<\/span><\/span>\u00a0<\/span><\/p>\n

\"\"<\/a><\/p>\n

Storing the last value in the global context<\/span><\/b>\u00a0<\/span><\/h4>\n

Whilst in the Victron Client configuration, you may also notice the new \u201cContext store\u201d option. Enabling this will result in the node storing the last seen value into the global context. This is a way to store information that can be shared between different nodes without using the messages that pass through a flow.\u00a0<\/span>\u00a0<\/span><\/p>\n

\"\"<\/div><\/a><\/p>\n

The values are stored under \u2018victronenergy\u2019 in an object containing all of the seen values. With this, you can fetch the latest value from the context by using a change node (or directly from a function node). Perhaps not everyone will want to use this, but it can simplify your flows.\u00a0<\/span>\u00a0<\/span><\/p>\n

The above picture shows that my current flows have 3 input nodes:<\/span>\u00a0<\/span><\/p>\n