UPS INSTALLATION PLAN AND UNPACKINGEaton 9395 550/275 UPS (225–550 kVA) Installation and Operation Manual 164201716 Rev 2 www.eaton.com/powerquality 3-73.2.2 UPS System Power Wiring PreparationRead and understand the following notes while planning and performing theinstallation: Refer to national and local electrical codes for acceptable external wiring practices. To allow for future kVA upgrades, consider installing a derated UPS using wiringand external overcurrent protection breakers sized for a fully rated UPS. For external wiring, use 90°C copper or aluminum wire. Wire sizes listed inTable 3‐4 and Table 3‐6 are for copper wiring only. If wire is run in an ambienttemperature greater than 30°C, higher temperature wire and/or larger size wiremay be necessary. Wire sizes are based on using the specified breakers. Wire ampacities are chosen from Table 310-16 of the National Electrical Code®(NEC®). Specification is for copper wire with a 90°C rating. Material and labor for external wiring requirements are to be provided bydesignated personnel. If installing a maintenance bypass, a minimum of two separate feeds withupstream feeder breakers, or a single feed with two upstream feeder breakers,must be provided: one for the UPS or rectifier input breaker (RIB) (if installed) andone for the maintenance bypass input. DO NOT use a single feed or a single feederbreaker to supply both the UPS or RIB and the maintenance bypass. If a bypassinput breaker (BIB) is installed in the maintenance bypass and a single-feed UPS isbeing installed, a single feed to the maintenance bypass is acceptable for supplyingboth the UPS and the bypass. The bypass feed into this equipment uses three or four wires. The rectifier feedinto this equipment uses three wires. The phases must be symmetrical aboutground (from a Wye source) for proper equipment operation. If the load requires a neutral, a bypass source neutral must be provided. If the loaddoes not require a neutral and there is no neutral conductor connected at thebypass input, a neutral to ground bonding jumper must be installed. DO NOT installboth a source neutral and a bonding jumper. See Table 3‐4 or Table 3‐6 for neutralbonding jumper wire sizes. The bonding jumper must be copper wire.C A U T I O NHIGH IMPEDANCE GROUND SOURCES - If the supply source is a high impedance ground (IT) type, the inputneutral conductor must be connected from the source of supply. If there is no output neutral connected tothe UPS, the neutral‐forming transformer kit may be used instead of pulling a neutral from the source. If theload requires a neutral, then an input neutral conductor must be pulled into the UPS. In no circumstancesshall a neutral to ground bonding jumper be installed in the UPS.C A U T I O NDELTA SOURCES (TN‐S) - The 9390 UPS system can be operated only from a delta supply source that is fullyfloating and if the neutral‐forming transformer kit is installed in the UPS. The UPS cannot be operated from amid‐point or end‐point grounded delta supply source. With this type of supply source, there is no capabilityto provide an output neutral. In no circumstances shall a neutral to ground bonding jumper be installed in theUPS. The UPS cabinet is shipped with a debris shield covering the ventilation grill on topof the unit. Do not remove the debris shield until installation is complete. However,remove the shield before operating the UPS. Once the debris shield is removed, donot place objects on the ventilation grill.
