UPS Installation Plan and UnpackingEaton 9E UPS (20–30 kVA, 208/220V) Generation 3 Installation and Operation Manual P-164000301—Rev 1 www.eaton.com/powerquality 3-11The line-to-line unbalanced output capability of the UPS is limited only by the full load per phase current valuesfor AC output to critical load shown in Table 3-5. The recommended line-to-line load unbalance is 50% or less.Bypass and output overcurrent protection and bypass and output disconnect switches are to be supplied bythe customer. Table 3-9 lists the recommended rating for bypass and output circuit breakers.Battery voltage is computed at 2 volts per cell as defined by Article 480 of the NEC. Rated battery current iscomputed based on 2 volts per cell.3.2.3 UPS System Interface Wiring PreparationControl wiring for features and options should be connected at the customer interface terminal blocks locatedinside the UPS.WARNINGDo not directly connect relay contacts to the mains related circuits. Reinforced insulation to themains is required.Read and understand the following notes while planning and performing the installation:l Use Class 1 wiring methods (as defined by the NEC) for interface wiring from 30V to 600V. The wire shouldbe rated for 600V, 1A minimum. 12 AWG maximum wire size.l Use Class 2 wiring methods (as defined by the NEC) for interface wiring up to 30V. The wire should be ratedfor 24V, 1A minimum.l Because of the REPO and building alarm wiring route in the UPS cabinet, the wire should be rated for aminimum of 300V.l Use twisted-pair wires for each input and return or common.l All interface wiring and conduit is to be supplied by the customer.l When installing external interface wiring between a REPO or building alarm and the UPS interface terminals,conduit must be installed between each device and the UPS cabinet.l Interface wiring can be installed using conduit through the bottom of power terminal cover base or byrouting wiring through the power terminal cover base wiring channels between the UPS and SIAC-B, IAC-T,or IAC-TB.l If using the power terminal wiring channel, keep interface wiring separate from power wiring or use shieldedwire.l If using conduit, install the interface wiring in separate conduit from the power wiring.l All building alarm inputs require an isolated normally-open contact or switch (rated at 24 Vdc, 20 mAminimum) connected between the alarm input and common terminal. All control wiring and switch contactsare customer-supplied.l LAN and telephone drops for use with Mini-Slot connectivity cards must be supplied by the customer.Table 3-9. Recommended Bypass and Output Circuit Breaker RatingsOutput RatingUPS Model Load Rating 208/220VEaton 9E–20Eaton 9E–30/2080% Rated 100A100% Rated 80AEaton 9E–30/30 80% Rated 125A100% Rated 100A