SmartSlot Customize UPS capabilities with management cards. Cold-start capable Provides temporary battery power when the utility power is out. Serial Connectivity Use any Home Automation network to monitor and control the S20 through its RS-232 serial port. For information on how to communicate with the S20, see APC's Application Note #102. Crestron and AMX installers should visit their respective websites for information on how to integrate the S20 into those networks. Resettable circuit breakers Enables a quick recovery from overload events. Hot-swappable batteries Ensures clean, uninterrupted power to protected equipment while batteries are being replaced Disconnected battery notification Warns when a battery is not available to provide backup power. Automatic self-test Periodic battery self-test ensures early detection of a battery that needs to be replaced. Adjustable voltage-transfer points Maximizes useful battery life by widening the input voltage window or tightening the output voltage regulation. Adjustable voltage sensitivity Provides the ability to adapt the UPS for optimal performance in specific power environments or generator applications. Audible alarms Provides notification of changing utility power and UPS conditions. Serial Connectivity Provides management of the UPS via a serial port. Temperature-compensated battery charging Prolongs battery life by regulating the charge voltage according to battery temperature. Boost and Trim Automatic Voltage Regulation (AVR) Gives higher application availability by correcting low and high voltage conditions without using the battery. Intelligent battery management Maximizes battery performance, life, and reliability through intelligent, precision charging. Safety-agency approved Ensures the product has been tested and approved to work safely with the connected service provider equipment and within the specified environment. UL, FCC, CE, C-Tick approvals. Rack/Tower convertible Protects the initial investment in the UPS when migrating from tower to rack-mount environment. Network manageable Provides remote management of the UPS over the network. Adjustable voltage sensitivity Provides the ability to adapt the Power Conditioner for optimal performance in specific power environments or generator applications. LED status indicators Quickly understand unit and power status with visual indicators.