ENGLISH OWNER’S MANUAL NETWORK MONITOR Please read this manual carefully before operating your set and retain it for future reference. NETWORK MONITOR MODEL N1941ML www.lg.com Accessories !!! Thank for selecting LGE products !!! Please make sure the following items are included with your monitor. If any items are missing, contact your dealer. User's Guide/Cards 15-pin D-Sub Signal Cable (To set it up, this signal cable may be attached to this product before shipping out.) Power Cord (Depending on the country) IMPORTANT This accessories may look different from those shown here. User must use shielded signal interface cables (D-sub 15 pin cable) with ferrite cores to maintain standard compliance for the product. Important Precautions This unit has been engineered and manufactured to ensure your personal safety, however improper use may result in potential electrical shock or fire hazards. In order to allow the proper operation of all safeguards incorporated in this display, observe the following basic rules for its installation, use, and servicing. On Safety Use only the power cord supplied with the unit. In case you use another power cord, make sure that it is certified by the applicable national standards if not being provided by the supplier. If the power cable is faulty in any way, please contact the manufacturer or the nearest authorized repair service provider for a replacement. The power supply cord is used as the main disconnection device. Ensure that the socket-outlet is easily accessible after installation. Operate the display only from a power source indicated in the specifications of this manual or listed on the display. If you are not sure what type of power supply you have in your home, consult with your dealer. Overloaded AC outlets and extension cords are dangerous. So are frayed power cords and broken plugs. They may result in a shock or fire hazard. Call your service technician for replacement. As long as this unit is connected to the AC wall outlet, it is not disconnected from the AC power source even if the unit is turned off. Do not Open the Display: There are no user serviceable components inside. There are Dangerous High Voltages inside, even when the power is OFF. Contact your dealer if the display is not operating properly. To Avoid Personal Injury : Do not place the display on a sloping shelf unless properly secured. Use only a stand recommended by the manufacturer. Do not drop an object on or apply impact to the product. Do not throw any toys or objects on the product screen. It can cause injury to human, problem to product and damage the display. To Prevent Fire or Hazards: Always turn the display OFF if you leave the room for more than a short period of time. Never leave the display ON when leaving the house. Keep children from dropping or pushing objects into the display's cabinet openings. Some internal parts carry hazardous voltages. Do not add accessories that have not been designed for this display. When the display is to be left unattended for an extended period of time, unplug it from the wall outlet. In the presence of thunder and lightning, never touch the power cord and signal cable because it can be very dangerous. It can cause electric shock. A1 Important Precautions On Installation Do not allow anything to rest upon or roll over the power cord, and do not place the display where the power cord is subject to damage. Do not use this display near water such as near a bathtub, washbowl, kitchen sink, laundry tub, in a wet basement, or near a swimming pool. Displays are provided with ventilation openings in the cabinet to allow the release of heat generated during operation. If these openings are blocked, built-up heat can cause failures which may result in a fire hazard. Therefore, NEVER: Block the bottom ventilation slots by placing the display on a bed, sofa, rug, etc. Place the display in a built-in enclosure unless proper ventilation is provided. Cover the openings with cloth or other material. Place the display near or over a radiator or heat source. Do not rub or strike the Active Matrix LCD with anything hard as this may scratch, mar, or damage the Active Matrix LCD permanently. Do not press the LCD screen with your finger for a long time as this may cause some afterimages. Some dot defects may appear as Red, Green or Blue spots on the screen. However, this will have no impact or effect on the display performance. If possible, use the recommended resolution to obtain the best image quality for your LCD display. If used under any mode except the recommended resolution, some scaled or processed images may appear on the screen. However, this is characteristic of the fixed-resolution LCD panel. Leaving a fixed image on the screen for a long time may cause damage to the screen and cause image burn-in. Make sure to use a screen saver on the product. Burn-in and related problems are not covered by the warranty on this product. Do not shock or scratch the front and sides of the screen with metallic objects. Otherwise, it may cause damage to the screen. Make sure the panel faces forward and hold it with both hands to move. If you drop the product, the damaged product can cause electric shock or fire. Contact an authorized the service center for repair. Avoid high temperatures and humidity. For displays with glossy bezels the user should consider the placement of the display as the bezel may cause disturbing reflections from surrounding light and bright surfaces. A2 Important Precautions On Cleaning Unplug the display before cleaning the face of the display screen. Use a slightly damp (not wet) cloth. Do not use an aerosol directly on the display screen because over-spraying may cause electrical shock. When cleaning the product, unplug the power cord and scrub gently with a soft cloth to prevent scratching. Do not clean with a wet cloth or spray water or other liquids directly onto the product. An electric shock may occur. (Do not use chemicals such as benzene, paint thinners or alcohol) Spray water onto a soft cloth 2 to 4 times, and use it to clean the front frame; wipe in one direction only. Too much moisture may cause staining. On Repacking Do not throw away the carton and packing materials. They make an ideal container in which to transport the unit. When shipping the unit to another location, repack it in its original material. On Disposal (Only , Hg lamp used LCD Monitor) The fluorescent lamp used in this product contains a small amount of mercury. Do not dispose of this product with general household waste. Disposal of this product must be carried out in accordance to the regulations of your local authority. A3 Connecting the Display Before setting up the monitor, ensure that the power to the monitor, the computer system, and other attached devices is turned off. Connecting the stand 1. Place the monitor with its front facing downward on a soft cloth. 2. Assemble the Stand Body into the product in the correct direction as shown in the picture. Make sure you push it until you hear it “click”. Hinge Body Stand Body 3. Assemble the Stand Base(Front, Rear) into the Stand Body in the correct direction. Stand Body Stand Base 4. Tie down the base lock to perpendicularity direction. 5. Once assembled take the monitor up carefully and face the front side. Important This illustration depicts the general model of connection. Your monitor may differ from the items shown in the picture. Do not carry the product upside down holding only the stand base. The product may fall and get damaged or injure your foot. A4 Connecting the Display Disassembling the stand 1. Put a cushion or soft cloth on a flat 2. Place the monitor face down on the surface. 3. cushion or soft cloth. Change your lock on the product as it follows and turn it in the arrow direction. If you can't release the stand base even the locking knob is at a release position, Please push the indicated knob down and retry it. 4. Pull out the stand to remove. A5 Connecting the Display 5. Pushing the PUSH button, take the stand base from stand body. Warning: You can hurt your finger. Good Position Bad Position Before setting up the monitor, ensure that the power to the monitor, the computer system, and other attached devices is turned off. Positioning your display 1. Adjust the position of the panel in various ways for maximum comfort. Tilt Range : -5˚~20˚ When adjusting the angle of the screen, do not put your finger(s) in between the head of the monitor and the stand body. You can hurt your finger(s). Ergonomic It is recommended that in order to maintain an ergonomic and comfortable viewing position, the forward tilt angle of the monitor should not exceed 5 degrees. A6 Connecting the Display Using the Computer NOTE This is a simplified representation of the rear view. This rear view represents a general model; your display may differ from the view as shown. 1. A Connect D-sub(RGB Analog) Cable (PC) B Connect D-sub(RGB Analog) Cable (Mac) Analog signal Wall-outlet type Mac adapter (This item must be purchased separately.) X350 PCI Card X550 PCI Card For Apple Macintosh use, a separate plug adapter is needed to change the 15 pin high density (3 row) D-sub VGA connector on the supplied cable to a 15 pin 2 row connector. 2. Press button on the front switch panel to turn the power on. When monitor power is turned on, the 'Self Image Setting Function' is executed automatically. NOTE ‘ Self Image Setting Function’? This function provides the user with optimal display settings.When the user connects the monitor for the first time, this function automatically adjusts the display to optimal settings for individual input signals. ‘AUTO/SET’ Function? When you encounter problems such as blurry screen, blurred letters, screen flicker or tilted screen while using the device or after changing screen resolution, press the AUTO/SET function button to improve resolution. A7 Connecting the Display Using the Monitor 1. Make sure to turn off the computer and product. Connect the cable as below sketch map form 1 to 2 . 1 Connect peripheral devices 2 Connect LAN Cable (X350/550 port) Analog signal Wall-outlet type X350 PCI Card X550 PCI Card (Make sure to connect X350/550 port,not LAN port of PC) Keyboard/Mouse Input LAN cable should be connected before booting PC.(This item must be purchased separately.) X350/550 port Up to 5 ports are supported per X550 PCI Card. Up to 5 ports can be connected if necessary. (This item must be purchased separately.) X350 PCI Card:3 ports X550 PCI Card:5 ports When you use the monitor speaker via the X-PORT, turn the PC volume up to the highest level and adjust the monitor volume. It is recommended to use a PS/2-type keyboard/mouse. To use the monitor keyboard/mouse properly, monitor must be connected to the PC. Applications that require other than 16 bit color quality and the set resolution are not supported. ‘AUTO/SET’ Function? When you encounter problems such as blurry screen, blurred letters, screen flicker or titled screen while using the device or after changing screen resolution, press the AUTO/SET function button to improve resolution. 2. Press button on the front switch panel to turn the power on. A8 Connecting the Display NOTE LAN Cable -For the LAN cable,it is recommended to use SFTP(recommend : 6m,max : 10m) provided by LG. Image quality and some functionality may be degraded if a different LAN cable is used. -To achieve good image quality,avoid using UTP and STP cables. -You must use a direct LAN cable,not a crossover one. Both connections should be same colors. Do not connect any kind of network devices. Core The ferrite core can be used to reduce electromagnetic waves when connecting a LAN cable. As shown in the image below,fit the ferrite core to the LAN cable. The ferrite core needs to be separated from the mold by 5 centimeters. You can purchase SFTP(recommend : 6m,max : 10m)LAN cables and cores through LG additionally. 50 10mm 50 10mm A9 Connecting the Display Connecting to a X350/550 port using a LAN cable. Notice Turning the power off while booting the PC may damage the product. Turning the power off while booting the PC may cause it to operate incorrectly. If the mouse is connected using a USB device and is not detected, disconnect and connect it again. If you reconnect a peripheral device such as a keyboard, mouse or LAN cable while the PC is in operation, the device may not work properly. Make sure that the power is turned off when disconnecting/connecting a peripheral device. Making both ends of LAN cable to across the coil two times before connect to network monitor and PC. PC spec : The host PC operating system can be Windows Server 2003 R2 SP2(Standard or Enterprise Edition, 32-bit). Notice (in case of using X550) - To achieve the best PC performance, up to six users are recommended for one PC. If there are seven or more users, performance may be degraded depending on the environment and the PC’s specifications. - Check if the PC supports Windows Server 2003 before purchasing it. A host PC should have the following specifications: 1. Minimum - CPU : Dual core processor at 3.0 GHz or higher (i.e. : Intel Core 2 Duo or AMD Athlon X2) - RAM : 2 GB of system memory or higher 2. Recommend - CPU : Quad core processor at 2.66 GHz or higher (i.e. Intel Core 2 Quad or AMD Phenom X4) - RAM : 4 GB of system memory 3. Internet access speed may be different depending on the network environment. Restrictions : Using this network monitor for the following purposes may cause screen disruption or slower PC operation. 1. Video / Moving picture 2. Games Color setting: Image quality may vary depending on the X350/550 card, so it is recommended to execute “White Balance” when using the product as a network monitor after connecting a LAN cable for the first time. Refer to A18 for more information on White Balance. If you use the monitor with a X-PORT input, image quality and resolution may be poorer than with a D-sub input. ( Only 16 bit color is supported for X-PORT input.) A10 Control Panel Functions Front Panel Controls Control MUTE Button Function • X-PORT : This menu is available, use this button to switch the sound on or off. or <mute on> <mute off> • D-sub : This menu is not available. MENU Button Use this button to enter or exit the On Screen Display. OSD LOCKED/UNLOCKED This function allows you to lock the current control settings, so that they cannot be inadvertently changed. Press and hold the MENU button for several seconds. The message "OSD LOCKED" should appear. You can unlock the OSD controls at any time by pushing the MENU button for several seconds. The message "OSD UNLOCKED" should appear. A11 Control Panel Functions Control SOURCE Function Use these buttons to select or adjust functions in the On Screen Display. Use this button to make either D-Sub or X-PORT connector active. This feature is used when two input sources are connected to the display. VOLUME Use these buttons to select or adjust functions in the On Screen Display. Use buttons to decrease or increase the earphone volume on X-PORT input. AUTO/SET Button Use this button to enter a selection in the On Screen Display. AUTO IMAGE ADJUSTMENT When adjusting your display settings, always press the AUTO/SET button before entering the On Screen Display(OSD). This will automatically adjust your display image to the ideal settings for the current screen resolution size (display mode). The best display mode is 1360 x 768 Power Button Use this button to turn the display on or off. Power Indicator This Indicator lights up blue when the display operates normally(On Mode). If the display is in Sleep Mode (Energy Saving), this indicator color changes to flicker. A12 On Screen Display (OSD) Control Adjustment Screen Adjustment Making adjustments to the image size, position and operating parameters of the display is quick and easy with the On Screen Display Control system. A short example is given below to familiarize you with the use of the controls. The following section is an outline of the available adjustments and selections you can make using the OSD. NOTE Allow the display to stabilize for at least 30 minutes before making image adjustments. To make adjustments in the On Screen Display, follow these steps: Press the MENU Button, then the main menu of the OSD appears. To access a control, use the or Buttons. When the icon you want becomes highlighted, press the AUTO/SET Button. Use the / Buttons to adjust the image to the desired level. Use the AUTO/SET Button to select other sub-menu items. Push the MENU Button once to return to the main menu to select another function. Push the MENU Button twice to exit from the OSD. A13 On Screen Display(OSD) Selection and Adjustment The following table indicates all the On Screen Display control, adjustment, and setting menus. ( : Adjustable A : D-SUB Input X : X-PORT Input ) Main menu PICTURE Sub-menu A BRIGHTNESS GAMMA sRGB 6500K 9300K PRESET Reference To adjust the brightness, contrast and gamma of the screen CONTRAST COLOR X To customize the color of the screen RED GREEN POSITION BLUE HORIZONTAL TRACKING VERTICAL CLOCK To adjust the position of the screen To improve the clarity and stability of the screen PHASE SHARPNESS SETUP LANGUAGE OSD To customize the screen status for a user's operating environment HORIZONTAL POSITION VERTICAL WHITE BALANCE POWER INDICATOR 4:3 IN WIDE FACTORY RESET F ENGINE MOVIE To select or customize desired image settings INTERNET USER ACE RCM NORMAL DEMO NOTE The order of icons may differ depending on the model (A14~A19). A14 On Screen Display(OSD) Selection and Adjustment You were introduced to the procedure of selecting and adjusting an item using the OSD system. Listed below are the icons, icon names, and icon descriptions of the all items shown on the Menu. Press the MENU Button, then the main menu of the OSD appears. Main Menu MENU : Exit : Adjust (Decrease/Increase) SET : Enter Menu Name : Select another sub-menu : Restart to select sub-menu Button Tip Menu Name Sub-menus Icons NOTE OSD (On Screen Display) menu languages on the monitor may differ from the manual. A15 On Screen Display(OSD) Selection and Adjustment Main menu Sub menu Description PICTURE BRIGHTNESS To adjust the brightness of the screen. CONTRAST To adjust the contrast of the screen. GAMMA Set your own gamma value. : -50/0/50 On the monitor, high gamma values display whitish images and low gamma values display blackish images. MENU : Exit : Decrease : Increase SET : Select another sub-menu COLOR PRESET Select the screen color. • sRGB: Set the screen color to fit the SRGB standard color specification. • 6500K: Slightly reddish white. • 9300K: Slightly bluish white. RED Set your own red color levels. GREEN Set your own green color levels. MENU : Exit BLUE : Decrease : Increase SET : Select another sub-menu Set your own blue color levels. A16 On Screen Display(OSD) Selection and Adjustment Main menu Sub menu Description POSITION HORIZONTAL To move image left and right. VERTICAL To move image up and down. MENU : Exit : Decrease : Increase SET : Select another sub-menu TRACKING MENU : Exit : Decrease : Increase SET : Select another sub-menu CLOCK To minimize any vertical bars or stripes visible on the screen background. The horizontal screen size will also change. PHASE To adjust the focus of the display. This item allows you to remove any horizontal noise and clear or sharpen the image of characters. SHARPNESS To adjust the clearness of the screen. A17 On Screen Display(OSD) Selection and Adjustment Main menu Sub menu LANGUAGE To choose the language in which the control names are displayed. OSD POSITION To adjust position of the OSD window on the screen. WHITE BALANCE If the output of the video card is different from the required specifications, the color level may deteriorate due to video signal distortion. Using this function, the signal level is adjusted to fit into the standard output level of the video card in order to provide the optimal image. Activate this function when white and black colors are present in the screen. POWER INDICATOR Use this function to set the power indicator on the front side of the monitor to ON or OFF. If you set OFF, it will go off. If you set ON at any time, the power indicator will automatically be turned on. 4:3 IN WIDE Use this function to select the image size of the screen. SETUP MENU : Exit : Adjust : Adjust SET : Select another sub-menu Description WIDE 4:3 • WIDE : Switch to full screen mode according to input image signal. • 4 : 3 : Change the image signal ratio into 4:3. Restore all factory default settings except "LANGUAGE" . Press the , buttons to reset immediately. FACTORY RESET If this does not improve the screen image, restore the factory default settings. If necessary, perform the white balance function again. This function will be enabled only when the input signal is a D-sub or X-PORT input signal. A18 On Screen Display(OSD) Selection and Adjustment Main menu Sub menu Description MOVIE This feature lets you easily select the best desired INTERNET image condition optimized to the environment (ambient illumination, image types etc). MOVIE: For animation images in videos or movies INTERNET: For text images (Word processing etc.) MENU : Exit : Decrease : Increase SET : Select another sub-menu USER User You can manually adjust ACE or RCM. You can save or restore the adjusted value even when using a different environment. ...ACE(Adaptive Clarity Enhancer): Selects the clarity mode. ...RCM(Real Color Management): Selects the color mode. Not applied Green enhance Flesh tone Color Enhance NORMAL This is under normal operating conditions. DEMO This is just for advertising to customer in the shops. It’s setting is same with Movie mode and screen is divided by half. The INTERNET and NORMAL features become enabled for X-PORT input. A19 Troubleshooting Check the following before calling for service. No image appears ● Is the power cord of the • Check and see if the power cord is connected properly to the power outlet. display connected? ● Is the power indicator light on? • Press the Power button. ● Is the power indicator flickering? • If the display is in power saving mode, try moving the mouse or pressing any key on the keyboard to bring up the screen. • Try to turn on the PC. ● Do you see an "OUT OF • This message appears when the signal from the PC (video card) is out of horizontal or vertical RANGE" message on frequency range of the display. See the the screen? 'Specifications' section of this manual and configure your display again. ● Do you see a "CHECK SIGNAL CABLE" message on the screen? • This message appears when the signal cable between your PC and your display is not connected. Check the signal cable and try again. Do you see a "OSD LOCKED" message on the screen? ● Do you see “OSD LOCKED” when you push MENU button? • You can secure the current control settings, so that they cannot be inadvertently changed. You can unlock the OSD controls at any time by pushing the MENU button for several seconds: the message “OSD UNLOCKED” will appear. A20 Troubleshooting Display image is incorrect ● Display Position is incorrect. • Press the AUTO/SET button to automatically adjust your display image to the ideal setting. If the results are unsatisfactory, adjust the image position using the H position and V position icon in the on screen display. ● On the screen background, vertical bars or stripes are visible. • Press the AUTO/SET button to automatically adjust your display image to the ideal setting. If the results are unsatisfactory, decrease the vertical bars or stripes using the CLOCK icon in the on screen display. ● Any horizontal noise appearing in any image or characters are not clearly portrayed. • Press the AUTO/SET button to automatically adjust your display image to the ideal setting. If the results are unsatisfactory, decrease the horizontal bars using the PHASE icon in the on screen display. • Check Control Panel --> Display --> Settings and adjust the display to the recommended resolution or adjust the display image to the ideal setting. Set the color setting higher than 24 bits (true color).(Only for D-SUB input) Important Check Control Panel --> Display --> Settings and see if the frequency or the resolution were changed. If yes, readjust the video card to the recommend resolution. (Only for D-SUB input) The setting method can differ by computer and O/S (Operation System), and resolution mentioned above may not be supported by the video card performance. In this case, please ask to the computer or the video card manufacturer. (Only for D-SUB input) If the recommended resolution (optimal resolution) is not selected, letters may be blurred and the screen may be dimmed, truncated or biased. Make sure to select the recommend resolution. A21 Troubleshooting Display image is incorrect ● The screen color is mono or abnormal. • Check if the signal cable is properly connected and use a screwdriver to fasten if necessary. • Make sure the video card is properly inserted in the slot. • Set the color setting higher than 24 bits (true color) at Control Panel - Settings. (X-PORT support only 16bits color) - “White Balance” is performed on black/white pattern. - Check if the screen is set to normal mode. ● The screen blinks. • Check if the screen is set to interlace mode and if yes, change it to the recommend resolution. - Check if the screen is set to normal mode. A22 Specifications N1941ML Display 47.0 cm Flat Panel Active matrix-TFT LCD, Anti-Glare coating Visible diagonal size: 47.0 cm 0.30*0.30 mm pixel pitch Sync Input D-SUB Video Input Resolution Horizontal Freq. 30 - 66 kHz (Automatic) Vertical Freq. 57 - 63 Hz (Automatic) D-SUB support 60Hz only(except Dos mode) X-PORT 1440 x 900 (60Hz) 1280 x 720 (60Hz) 1360 x 768 (60Hz) 800 x 600 (72Hz) 1024 x 768 (60Hz) D-SUB Signal Input 15 pin D-Sub Connector Input Form RGB Analog (0.7 Vp-p/ 75 ohm) X-PORT Signal Input X-PORT Connector Input Form X-PORT Signal Max VESA 1360 x 768 @60 Hz Recommend VESA 1360 x 768 @60 Hz Plug&Play DDC 2B (Only for D-SUB Input) Power Consumption On Mode Sleep Mode Off Mode Dimensions & Weight Length Width Depth Net : ≤ ≤ 15 W(Typ.) 1W 1W With Stand 370.9 mm 448 mm 198 mm 2.7 kg Without Stand 278 mm 448 mm 58 mm Tilt Range Tilt Power Input AC 100-240V~ 50/60Hz 0.8A Operating Conditions Temperature 10˚C to 35 ˚C Humidity 10 % to 80 % non-Condensing Storage Conditions Temperature -20˚C to 60 ˚C Humidity 5 % to 90 % non-Condensing Environmental Conditions Stand Base Power cord Attached ( -5˚~ 20˚ ), Detached ( O ) Wall-outlet type NOTE Information in this document is subject to change without notice. A23 Specifications D-SUB Preset Modes (Resolution) Display Modes (Resolution) 1 2 3 4 *5 Horizontal Freq. (kHz) 31.468 31.469 37.879 48.363 47.712 720 x 400 640 x 480 800 x 600 1024 x 768 1360 x 768 Vertical Freq. (Hz) 70 60 60 60 60 *Recommend Mode X-PORT Preset Modes (Resolution) Display Modes (Resolution) 1 2 3 *4 5 800 x 600(72Hz) 1024 x 768(60Hz) 1280 x 720(60Hz) 1360 x 768(60Hz) 1440 x 900(60Hz) *Recommend Mode Indicator MODE On Mode Sleep Mode Off Mode LED Color Blue Flicker Off A24 Installing the Wall mount plate This monitor satisfies the specifications of the Wall mount plate or the interchange device. 1. Place the monitor with its front facing downward on a soft cloth. 2. Separate the stand by pushing the PUSH button. Good Position Bad Position Warning: You can hurt your finger. A25 Installing the Wall mount plate 3. Install the Wall mount plate. Wall mount plate(Separate purchase) This is stand-type or wall mount type and is connectable with Wall mount plate. Please refer to the installation guide for more details, which is provided when Wall mount plate is purchased. Kensington Security Slot Connected to a locking cable that can be purchased separately at most computer stores. <Screw Mounting Interface Dimension> Hole spacing : 75 mm x 75 mm. NOTE VESA compatible only with respect to screw mounting interface dimensions and mounting screw specifications Please use VESA standard as below. * 784.8 mm and under (30.9 inch) - Wall Mount Pad Thickness : 2.6 mm - Screw : 4.0 mm x Pitch 0.7 mm x Length 10 mm * 787.4 mm and above (31.0 inch) - Please use VESA standard wall mount pad and screws. A26 Make sure to read the Safety Precautions before using the product. Keep the OWNER’S MANUAL(CD) in an accessible place for furture reference. The model and serial number of the SET is located on the back or one side of the SET. Record it below should you ever need service. MODEL SERIAL ENERGY STAR is a set of power-saving guidelines issued by the U.S.Environmental Protection Agency(EPA). As an ENERGY STAR Partner LGE U. S. A.,Inc. has determined that this product meets the ENERGY STAR guidelines for energy efficiency.