Timeline for How can I measure total current used
Current License: CC BY-SA 3.0
15 events
| when toggle format | what | by | license | comment | |
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| Apr 19, 2017 at 23:13 | comment | added | Festivejelly | @Finbar but it would tell me how many litres per hour would it not? Which is what im interested in. If I measured it over like 6 hours I can divide by 6 to get the milliamps per hour. This is so I can spec some batteries for my project. | |
| Apr 19, 2017 at 23:09 | vote | accept | Festivejelly | ||
| Apr 19, 2017 at 16:04 | answer | added | Neil_UK | timeline score: 2 | |
| Apr 19, 2017 at 15:53 | comment | added | Neil_UK | @Finbarr or in the case of the question here, "charge". If you're going to be picky, at least be right. | |
| Apr 19, 2017 at 15:48 | comment | added | Finbarr | Think of it like a river. Current is the rate at which water flows along the river, and it would have a given value at a given time - something like, say, 2000 litres a minute. What you are after would be the total amount of water that's flown through the river in a given space of time, such as overnight. That's not "total current", it's "volume". Or in the case of the question you're asking here, "energy". | |
| Apr 19, 2017 at 15:36 | comment | added | Festivejelly | The first comment answers my question really. A logging multimeter will do the trick. Pricey but I dont really care about the cost. Since I cant do it with a standard multimeter thats the choice. Or I could use one of those USB multimeters and splice the cables. to wire it into the circuit, let it run for an hour and see how much it has drained. | |
| Apr 19, 2017 at 15:34 | comment | added | Festivejelly | it really isnt meaningless though is it? Because thats the value I need to know. I cant stand there for 1 hour and physically measure the current draw. If the draw was uniform for the full hour then I could just measure it with a multimeter and work it out. But as I said the the frequency that the electromagnet turning on might vary. So If I can measure how much it draws then I can work out an average over a given time. I really dont think thats so hard to understand. | |
| Apr 19, 2017 at 15:25 | comment | added | Finbarr | "Milliamps per hour" IS meaningless. It's like saying "revolutions per minute per hour" | |
| Apr 19, 2017 at 15:06 | comment | added | Festivejelly | @Finbarr total current isnt meaningless at all. Itle give me the number of milliamps per hour which is exactly what I need. | |
| Apr 19, 2017 at 14:46 | comment | added | Oskar Skog | @12Lappie: P=E/t | |
| Apr 19, 2017 at 14:39 | comment | added | Festivejelly | I can work out the power consumed from the total current drawn. Thats fairly easy to do. What I need to know is the total current drawn from the battery over a given time. As I say I can measure it with a multimeter at the point in time. I guess I could estimate an average. The electromagnet will be on for 20ms so I suppose I could just guess how many times per hour itle be on. I would have prefered a logger that automatically did it though as over a few days I could build a more accurate measurement. | |
| Apr 19, 2017 at 14:33 | comment | added | 12Lappie | You cannot have what you call "Total current" since current is rate at which electrons are going through a medium. What you should look into is the total power consumed. | |
| Apr 19, 2017 at 14:19 | comment | added | Finbarr | "Current" is a rate of flow of charge, or combined with voltage gives you a rate of flow of energy so "Total current" is a rather meaningless concept. If the electromagnet always takes the same current, you could work out average current and/or total power by getting your arduino to record the amount of time it turns the electromagnet on for. | |
| Apr 19, 2017 at 14:15 | comment | added | winny | There exists logging multimeter which can measure the average current over long periods of time. They are pricey though. | |
| Apr 19, 2017 at 13:58 | history | asked | Festivejelly | CC BY-SA 3.0 |