Dollars & Sensors Training Video

To familiarize yourself with the new Dollars & Sensors Website and Mobile App, watch this short but critical training video that will teach you what's possible and the basics of how to use D&S.

Light Logger Introduction

The Light Logger records data regarding whether or not lights are on in a room (using a light sensor), and whether or not the room is occupied by one or more persons (using a motion sensor). This data is then analyzed to determine how much energy is typically wasted when people leave a room vacant, but with the lights left on.

The Logger is equipped with a clock, and it records the date & time whenever the lighting status changes (On/Off) or whenever the room occupancy status changes (Occupied/Vacant). It stores this data in Flash memory that can be read by plugging the Logger into any computer (Mac or PC) with a USB port. The Logger appears like an external drive, and all data is stored in a single text file on that drive called eslog.log. This website is then used to process and summarize the data inside eslog.log.

Logger Setup

Before using a Light Logger, there are a few critical steps you must follow to prepare the Logger for data collection.

1. Install Fresh Batteries
   The Logger is designed to log data for at least three weeks on a fully charged set of batteries. However, the batteries are still being used even when the device is not logging. So it's important to install fresh batteries before deploying a Light Logger in the field.


2. Set the Clock
   The Light Logger has an internal clock that must be set using your computer by running the Light Logger Utility provided below. The clock will only stay running when charged batteries are installed, so it's important to install batteries first and then set the clock on the Light Logger.


3. Clear Old Data
   The data on the Light Logger is stored in Flash memory, similar to a USB Flash drive (sometimes called a "Pen Drive" or "Thumb Drive"). The data is not lost when batteries die or are removed. Furthermore, the Light Logger's "drive" is protected so you can't accidentally delete or change the eslog.log file using your computer. The only way to delete the data is by using the Light Logger Utility provided below. It's important to clear this data before using the Logger in a new facility, otherwise you may confuse old data with new data.

Light Logger Utility

Download the Light Logger Utility v1.0
This is a small Microsoft Windows program that is required to set the clock on the Light Logger, and to clear all data on the Logger. It is compatible with Windows XP, Vista, and Windows 7. Download and run this utility now.

This utility requires that you have Microsoft's .NET 2.0 or greater installed. Almost all Windows computers have .NET 2.0 or greater already installed, so it's not likely that you will need to install it. If you do need to do so, Download Microsoft's .NET 3.5 Installer Here.

What do the Buttons and Lights Mean?

There are only two buttons on the Light Logger: START and STOP, and there are only two LED indicators: GREEN and RED. After you understand these two buttons and LEDs, you will know how to use your Logger. As you might expect, the START button is typically used to start logging data, and the stop button is used to stop logging data. But there are a few important nuances, because the Light Logger was designed to store up to 8 separate "Sessions" of data.

The ability to store multiple Sessions of data is important if you don't have many Light Loggers, and you would like to use one Logger to record data in multiple rooms, over the course of a long time period where you move the Logger from room to room. However, if you have enough Loggers to equip every room in your facility all at once, we strongly recommend just recording one Session of data with each Logger. This will help reduce confusion about which Sessions belong to which rooms.

If you have cleared all of the data on your Logger, the first Session of data is the #1 Session. If you stop that Session and begin anew, you are starting Session #2, and so on, up to #8. At any time, you can easily determine what Session # you are on by just quickly tapping either the START or STOP buttons:

• If the Logger is not presently logging, it will flash the GREEN LED when you tap either button. The number of times the GREEN LED flashes indicates the Session number of the next log Session. In other words, if you have cleared all of the data on your Logger, the GREEN LED will flash once, to indicate that it is ready to start logging Session #1.
  
  
• If the Logger is in the process of logging data, the RED LED will flash the Session # of the current Session. Even if you only intend to use your Logger for one Session of data, it's ok if you accidentally start a new (#2) Session. When processing the data later on, you'll have the chance to delete the mistaken Session #1 and only use the data from Session #2.

How Do I Start Logging Data?

Before you can begin a log Session, you must pass through the TEST mode. You enter this mode by holding down the START button for 3 seconds. As soon as you see the LEDs flash briefly on, the Logger is now in a special TEST mode where the GREEN LED will indicate whether the Logger thinks the lights are ON, and the RED LED will indicate when the Logger detects motion. This mode is crucial for determining that you've positioned the Logger in a place that is good for detecting both Light and Motion. See our tips below regarding Light Logger Placement.

Note that TEST mode only lasts for 60 seconds, after which the Logger returns to its resting state (Off). You can also manually exit TEST mode at any time by holding down the STOP button for 3 seconds.

While in TEST mode, you can then begin a log session by holding down the START button for 3 seconds. You will know the session has begun because the RED LED will flash the Session # when it begins logging data. But you are free to verify that the session has begun by tapping the START or STOP button, and if the Logger session is under way, the RED LED will flash the current Session #.

How Do I Stop Logging Data?

To stop logging data, first verify that the Logger is still recording data by tapping either START or STOP. If the Logger is still recording, it will flash the RED LED with the current session number. Now, simply hold down the STOP button for 3 seconds to stop this log Session. After 3 seconds, the RED LED will flash to indicate the Session # that just ended. And from here, you can tap either START or STOP to see the GREEN LED flash to indicate that the Logger is ready to start the next Session #, if desired. Thus, to confirm that you are done logging a single session of data (Session #1), you should be able to tap either START or STOP and see the GREEN LED flash twice, indicating that it is ready to start Session #2, should you desire.

Light Logger Placement

The Logger's light sensor responds primarily to rapid changes in ambient light level (such as when a light fixture turns on or off). For obtaining the most accurate readings, mount the Logger close to a fixture and away from sources of sunlight.

The motion sensor has a 360 degree field of view and can monitor an area up to 450 square feet, sensing up to 12 feet away (24ft diameter). Place the Logger where it will sense occupancy when someone is in the room, but where it will not detect hallway traffic. The motion sensor (PIR) monitors heat signatures, so be sure to mount the Logger away from HVAC ventilation vents (at least 6 feet away).

Keep Track of Your Loggers

Every Light Logger uses the same filename (eslog.log) to store its data. So it's important to keep track of which Logger you have installed in which room. You can do this by putting a temporary adhesive label on each Logger, and writing the Facility and Room Name on the label. Or you can keep a ledger where you write down the unique serial number on the back of the Logger, as well as the name of the Facility and the Room Name where it was installed.

Managing eslog.log Files

When you finish a large deployment of Light Loggers, you should create a folder on your computer's disk drive that is the name of the Facility where the Loggers were installed. Plug in each Light Logger and copy its eslog.log file to that folder. After copying the eslog.log file, you should rename it to the name of the room where the Logger was installed (e.g. "Office #1.log", "Closet.log", "Break Room.log"). The filenames are used by this website when generating reports from the files that you upload.

Using .zip Files

After you finish putting all of your .log files into a folder for the facility, it's a good idea to turn the entire folder into a single .zip file that contains all of the .log files. This will compress the data, but more importantly it will make it a one-step procedure to upload all of your .log files to your Projects stored on this website. This website will accept a single .zip file that contains many .log files. When you create a .zip file that contains many .log files, be sure you don't have more than one folder inside the .zip file. Create only one .zip for each facility that you are analyzing.

Understanding the Table Data

The Light Logger is used to collect energy usage data for several weeks in a row (recommended minimum of 2 weeks). The website reports summarize the average energy usage and savings for each day of the week, as well as summarizing the total projected Weekly and Annual energy usage and savings.

The most critical data is the amount of time that the room is Vacant, Lights ON (energy is being wasted), so this state is highlighted in this Table and Bar Chart. For each day of the week, you will see the average amount of time that energy is wasted (when several weeks of data are available, the total time for each day is averaged together for a more accurate estimate). Other lines in the table show the total average time for other room states. The columns on the right of the table are the total Weekly and Annual projected times for each room state.

The bottom line of the Table shows the percentage of energy savings that is projected after Leviton Occupancy Sensors are installed. This is calculated by taking the time that the room is Vacant, Lights ON and dividing it by the total time that the Lights are ON in the room. It's informative to review the savings for each day of the week, but the customer will be most interested in the % Savings projected for an entire year. This is the Annual % Savings that is shown in the bottom right corner of the table.

The Bar Chart is a way to visually assess the energy waste for each day of the week. The combined height of the bars represents the total amount of time that lights are on for any given day (total energy used for the day). The orange bar represents the number of hours that energy is being wasted (Vacant, Lights ON). The yellow bar represents the number of hours each day that energy is being used intentionally (Occupied, Lights ON). The Bar Chart is especially useful to quickly compare one Room (aka Session) of a facility against another Room. It's also useful when comparing a room of a facility against an entirely different facility.

Please Note: If the Light Logger records a partial day of data, that data will not be included in this report. The data is most accurate when a full 24hr day has been recorded. The Days Included indicates the total number of full 24hr days that were logged by the device. The more Days Included in the report, the more accurate the projected savings data will be.

Using the Data in Excel

To use the table data in Excel, use your mouse pointer to highlight the table data and then, Copy to the clipboard. With Excel open, select "Edit" and then, "Paste Special". Select Paste As "HTML", which should be the default.

Working with the Graph

The graph's y-axis represents hours. The maxmium value is automatically set to 12 or 24 hours depending on the data collected for that Session.

By moving your mouse over the graph columns, the daily occupancy and lighting values are displayed.

To use a graph image in an application such as PowerPoint, use your keyboard's "Print Screen" button. This will put a copy of the screen into your clipboard. From the clipboard, you can paste the page into any graphics or office application.

Printing from Your Browser

Each browser has its own Page Setup dialog box to let you set printing options. Be sure to check the option to include background images and colors for the most accurate print-out.