193.3.3 Rack InstallationThe DVR occupies 1.5U rack units of vertical rack space. Use twelve screws to fix the unit Please make sure the indoor temperature is below 35℃ (95°f). Please make sure there is 15cm (6 inches) space around the device to guaranteesound ventilation. Please install from the bottom to the top. If there are more accessories connected in the rack, please take precautionmeasures in case the rack power is overload.3.4 Connecting Power SupplyPlease check input voltage and device power button match or not.We recommend you use UPS to guarantee steady operation, DVR life span, and otherperipheral equipment operation such as cameras.3.5 Connecting Video Input and Output Devices3.5.1 Connecting Video InputThe video input interface is BNC. The input video format includes: PAL/NTSC BNC(1.0VBP- P , 75Ω.).The input video format: BNC(0.8VP-P,75Ω),The video signal should comply with your national standards.The input video signal shall have high SNR, low distortion; low interference, natural colorand suitable lightness.Guarantee the stability and reliability of the camera signal:The camera shall be installed in a cool, dry place away from direct sunlight, inflammable,explosive substances and etc.The camera and the DVR should have the same grounding to ensure the normaloperation of the camera.Guarantee stability and reliability of the transmission linePlease use high quality, sound shielded BNC. Please select suitable BNC modelaccording to the transmission distance.If the distance is too long, you should use twisted pair cable, and you can add videocompensation devices or use optical fiber to ensure video quality.You should keep the video signal away from the strong electromagnetic interference,especially the high tension current.Keep connection lugs in well contactThe signal line and shielded wire should be fixed firmly and in well connection. Avoid dryjoint, lap welding and oxidation.3.5.2 Connecting Video OutputVideo output includes a BNC (PAL/NTSC, 1.0VP- P, 75Ω)output, a VGA output and aHDMI output.