EV Logger iPhone icon

EV Logger gives electric vehicle owners the ability to log data similar to how gas car drivers might log fueling and gas mileage. With the necessary data entered, it can calculate things like distance driven, energy use, and energy efficiency.

EV Logger is highly customizable, allowing drivers to record the data they care about quickly and easily.
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The various available electric vehicles, including both home-built conversions and full production electric vehicles, have a wide variety of ways to present information about the car to the driver. Even drivers of the same vehicle will have different approaches to what data they want to log. EV Logger is designed to be as flexible as possible.

Drivers can record as much or as little information as they want. Numerous data fields are supported, ready to be customized by the driver. Drivers choose which fields to record and the order they appear on the screen. Hide the fields you don't care about and rearrange fields to match the order you want to enter them.

Recording data can be as simple as recording the odometer and energy use for each charge, or as complex as recording detailed information about every charge and drive segment. It's up to the driver. EV Logger isn't telling you what you should record, it's just making it easy to record the data you care about.

Once data is recorded, it can be viewed in the app as well as exported for use in spreadsheets or other applications.

Getting Started

When EV Logger is first launched, it will prompt you to create a vehicle. Here you'll want to choose an instrumentation configuration that best matches your vehicle. This will determine which fields are available in log entries for this vehicle. If your vehicle model isn't listed, choose "General EV" which will give you all of the fields that makes sense for most electric vehicles using general purpose measurement units while excluding the fields that are unique to specific models.

Once you have configured your vehicle(s), you can begin entering records.

Log Entries

There are four types of log entries: Drive, Charge, Park and Reset.

entry list Drive entries gather information about a drive. This could be a single one-way drive to work, or a full day of driving with many trip segments. It's your choice how much detail you want to record. In fact, you can completely skip drive records if you just want to record charge sessions to track energy use, cost, or efficiency.
entry list Charge entries record information about a charge. If you're not recording drive information, you'll want to record odometer values here, otherwise EV Logger will pick up mileage numbers from the drive records.
entry list Park records are used when you leave the car parked for an extended period, not plugged in, and want to record things like how much charge was lost. You may not ever use these records, but they are available for completeness.
entry list Reset records tell EV Logger that you are restarting your logging after a period of not logging. Perhaps you only want to log data when you go on extended drives or road trips. A reset record tells EV Logger starting values for things like the odometer, and tells it not to scan back to older records to find starting values.

Recording Data

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EV Logger strives to make the data entry as fast and easy as possible. The goal is to only enter data that has changed since the last record. For this reason, unless otherwise labeled, the data fields in EV Logger are meant to be recorded at the end of the drive or charge.

For a drive record, there's no reason to enter the odometer at the start of the trip because it hasn't changed since the end of the previous log entry. Likewise, the state-of-charge at the beginning of a drive is probably the same as it was at the end of the previous drive or charge. If it is the same, there's no reason you should have to record it. For the values EV Logger calculates for you, it will scan back to previous records to find starting values for data fields where that makes sense.

If you're recording values from a dedicated utility meter to calculate energy use, the wall meter reading at the start of a charge is usually unchanged from the end of the previous charge, so you only need to record the value at the end of the charge.

Of course, there may be exceptions. If the car sat for a while between log entries, the state-of-charge may have changed enough that you want to record that, so there are fields to record the state-of-charge at the start of a drive. Likewise, if you have a dedicated wall meter for your charging station, but share the station between multiple EVs, you may want to record the start value of the wall meter if it's been used since last charging the vehicle you are logging.

Calculating Values

If you record certain basic data fields, EV Logger will automatically make some calculations for you.

For a drive record, if you record mileage (either the odometer or trip meter), it will compute drive distance. If you also record state-of-charge information, it will compute drive efficiency.

For a charge record, if you record mileage and energy use, it will compute wall-to-wheel energy use. Mileage can be recorded in either the charge records, or in drive records. Energy used in charging may be displayed by the car, available from the charging station, computed from a utility meter, or from a device like Kill-A-Watt or The Energy Detective.

Customizing Log Records

To get started you'll want to create a log entry. You may notice it has many more data fields than you want to record, or it may be missing some you want, and the order is probably not ideal for how you want to enter data. You can customize the data fields to better suit the data you want to record.

Create an entry to get started, save it, then tap on it to view the result. With a saved log entry showing, you can tap the Customize button to change the fields and their order. You can drag items around to change their order. Below the default fields, you'll see the "Hidden Items", fields which are not currently displayed for this record type. Drag fields you want from the hidden section up to the top section. Drag fields you don't want from the top section down into the hidden section.

Changing the available fields and order in one Drive record will change all Drive records. You can do the same to customize the fields shown in a Charge, Park or Reset record. Note that hiding a field doesn't delete any data you may have recorded for that field. If you want to see that data, just make that field visible again.

Exporting Log Data

If you navigate back to the list of vehicles, you'll find an "Email" button. Tapping that button will allow you email your EV Logger data. Send a Text Report (tab delimited text file) to import into a spreadsheet program. You can also send EV Logger's database file (SQLite format) which can be used as a backup of your data.


If you have questions about EV Logger or suggestions for improvements, please email [evlogger].