Energy Machines (EMV)

Compute heat-pump performance indicators for a refrigerant circuit.

The Energy Machines (EMV) integration computes heat-pump performance indicators for a refrigerant circuit — coefficients of performance, component powers, refrigerant mass-flows, and superheating/subcooling values — turning raw circuit readings into the figures you actually judge a heat pump by.

The calculation itself happens at Energy Machines. THMI’s job is to send them the circuit’s readings on a schedule, and to make the results available to your virtual tags.

Installing it

Find Energy Machines (EMV) under Integrations in the project — in Explore if it isn’t installed yet, in Installed once it is — and choose Install. You provide its settings during install, and can change them later from the integration’s page.

Settings

Leave Push interval empty to use the default of 60 seconds. That’s the right choice unless Energy Machines has told you otherwise: pushing faster than the underlying readings actually change costs bandwidth and gains nothing, and the performance indicators are averages over time anyway.

Circuit calculations

A circuit calculation is one refrigerant circuit’s worth of inputs. Each one you add appears under Circuit calculations on the integration’s page, and each is pushed independently on the push interval.

Add one with New calculation:

• Key — the calculation’s key at Energy Machines. It may contain only letters, numbers, dots, hyphens, and underscores, up to 255 characters. This is a machine identifier they match on, not a display name, so use whatever they specify rather than something readable.
• Enabled — whether this circuit is pushed. Disable a circuit that’s out of service instead of deleting it, so its configuration survives.
• Parameters — the circuit’s inputs. At least one is required.

Parameters

Each parameter maps one of Energy Machines’ expected input names onto a tag in your project:

• Key — the input’s name at Energy Machines. Letters, numbers, and underscores only, and it can’t start or end with an underscore. It has to match what they expect — a suction-pressure input named P_SUCTION at their end must be P_SUCTION here, not Suction pressure.
• Tag — the tag whose value is sent for that input.

Two rules keep a calculation unambiguous: a key can only appear once in a calculation, and a tag can only be used by one parameter in it. If you try to reuse either, you’re told so before you can save.

Using the results in scripts

Once installed, a virtual tag read script can emvStart a calculation for a circuit and read the latest results with emvGet. Create one virtual tag per indicator you want to keep, so each becomes an ordinary tag you can chart, alarm on, and put on a page.

Uninstalling

More → Uninstall on the integration’s page removes it. This permanently deletes all of the integration’s settings and data for the project — the plant key, every circuit calculation, and all their parameters — and can’t be undone. The virtual tags whose scripts call emvGet are not deleted, but they stop returning results.