Multipliers are a useful in-app setting that can help in a variety of situations. This setting will multiply the measured voltage from a Gen 2 by the set amount, by circuit/sensor.
Important Note - No "default" multipliers are needed for the Gen 2 since its measuring voltage directly. This means if you're using the Gen 2 on a 240V system, a default multiplier will not be needed since the Gen 2 already knows you're on a 240V system.
This is most commonly used in situations with multi-pole circuits being monitored with a single sensor. An example might be this: If you have a dual pole circuit w/ each line running 10A @ 120V, then each line would be pulling ~1.2kW of power. Instead of using two sensors, one on each circuit line, to capture the total usage of 2.4kW, you can add use a single sensor on one line and a 2.0 multiplier. That 2.0 multiplier will adjust the 120V to 240V and get you the same 2.4kW value to be shown in the app (on the single sensor).
Now, multipliers can be helpful to conserve sensor count in these situations, but assuming usage (by not using sensors) can have weird behaviors in the app - especially if the two (or three) lines using a multiplied value are not behaving equally. Imagine in the above situation that instead of both lines using 10A on each (@ 120V each), one was using 5A while the other using 10A. That means total usage for the entire circuit would only be 1.8kW instead of the multiplied/assumed value of 2.4kW if monitoring the 10A circuit with the 2.0 multiplier attached. That means that not only the 50A CT measurement in the app would be incorrect, but the difference would also show up as Balance down below. Details on Balance can be found here if needed. Since the 200A CT's would be measuring 1.8kW (as they're measuring mains directly) but the 50A CT would be showing 2.4kW - the resulting Balance value would be -600W (and shown in green if this was the only circuit).
Should I use a multiplier or not?
If unsure whether or not a multiplier is causing accuracy issues, best option is to add another 50A CT to the other line for a few days and compare their usage afterwards. If the two lines are behaving similarly then using a multiplier should work correctly. If they're showing different measurements after a certain period of time, then leaving two sensors on the circuit is probably best.
Multipliers can be helpful, but measuring usage directly (with sensors) will always be more accurate than assuming usage with this setting.
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This knowledge base is pretty new for the Emporia team. Our goal is to provide all of the information we can to help you manage your energy in better ways. If this article wasn't helpful, or we could be more clarifying on any points please reach out to the Customer Support team and we'll certainly work to improve these guides.
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