Introduction
1.3Options
A number of options are available from Emerson® for your UPS system. Some options are not available for all ratings. Described below are the most frequently provided options. Other options are available. Contact your Emerson sales representative for more information.
•Battery and Racks—The batteries provide power in the event of a power outage. The Liebert NX UPS can use a variety of battery types, provided the battery plant is designed for the UPS DC voltage range and the load requirements of your application.
•Battery Cabinets—Valve-regulated, lead-acid (VRLA) sealed batteries are available in matching cabinets for convenient installation and maintenance in otherwise unprotected space. Depending on the UPS module rating, two or more cabinets may be connected in parallel to provide the additional run time.
•Module Battery Disconnect—The UPS system utilizes a separate Module Battery Disconnect for remotely located batteries. A sensing circuit in the UPS module, set at the battery low voltage limit, trips the Module Battery Disconnect to safeguard the battery from excessive discharge. The Module Battery Disconnect has an undervoltage release mechanism designed to ensure that during any shutdown or failure mode all battery potential is removed from the UPS system.
•Maintenance Bypass—This switchboard provides make-before-break maintenance bypass. It includes: Maintenance Bypass Breaker (MBB) and Maintenance Isolation Breaker (MIB).
•Load Bus Synchronization—The Load Bus Sync (LBS) option keeps independent UPS systems (and therefore their critical load buses) in sync, even when the modules are operating on DC source or asynchronous AC sources. This means that critical loads connected to both load buses can switch seamlessly between the two.
•Temperature-CompensatedCharging—When the battery temperature exceeds a preset limit (typically 77°F [25°C]), this optional circuit proportionally reduces float charging voltage to prevent overcharging the battery.
•Battery Load Testing-When activated, this option forces the battery string to assume the load for a short period of time.
