Emerson 115-120 Manuel D’Utilisation

6. If a split bypass configuration is used, connect the AC input supply cables to the rectifier input 

terminals (A1-B1-C1-N1) and the AC bypass supply cables to the bypass input terminals 

(A2-B2-C2-N1) and tighten the connections to 240lb-in. (27N-m) (M10 Bolt). Ensure correct phase 

rotation.

7. Connect the system output cables between the UPS output busbars (A-B-C-N terminals) and the 

critical load and tighten the connections to 240lb-in. (27N-m) (M10 bolt).

The UPS internal batteries will be connected at the factory, EXCEPT the connections between the 

shelves and to the breaker.

Observe the battery cable polarity. Be sure that the battery connection is made with the cor-

rect polarity.

8. Refit all protective covers removed for cable installation.

Based on your site’s specific needs, the UPS may require auxiliary connections to manage the battery 

system (external battery circuit breaker, battery temperature sensor), communicate with a personal 

computer or provide alarm signaling to external devices or for Remote Emergency Power Off (REPO). 

Terminations for these functions are located at the front of the static bypass assembly. The main 

features are:

• Input and output dry contacts signal (one pair of contacts of relay)
• Emergency Power Off control (EPO)
• Environmental parameter input interface
• User communication (for data setting and user background monitor)
• Liebert IntelliSlot

®

 interface

• Temperature detect interface

NOTE
For split bypass operation, ensure that the busbars between bypass and rectifier inputs are 

Risk of electrical shock and arc flash. Can cause property damage, injury and death.
If the load equipment will not be ready to accept power when the commissioning engineer 

arrives, ensure that the system output cables are safely isolated.

Risk of electrical shock and arc flash. Can cause property damage, injury and death.
The DC bus is live when this internal battery connection is made. This connection is to be 

performed ONLY by Liebert Services at startup.