Emerson Liebert NX 50 and 60 Hz - Manual (Page 21)

Single Module UPS Installation
9
1.6.1 Cable Termination
Once the equipment has been finally positioned and secured, connect the power cables as described in
the following procedure.
Refer to the appropriate cable connection drawing in 5.0 - Installation Drawings.
1. Verify that the UPS equipment is isolated from its external power source and all the UPS power
isolators are open. Check that these supplies are electrically isolated and post any necessary
warning signs to prevent their inadvertent operation.
2. Open the door to the UPS cabinet and remove one of the two protective cover to gain access to the
desired connection bars.
• the lower protective cover houses the 60-200kVA connection bars
• the left protective cover houses the 30-40kVA connection bars
The protective cover on the UPS cabinet of 60 to 200kVA models must be removed after the
handles on the power isolators have been removed.
3. Connect the safety earth and any necessary bonding earth cables to the copper earth busbar
located on the floor of the equipment below the power connections. All cabinets in the UPS must
be connected to the user’s ground connection.
Identify and make power connections for incoming cables according to one of the two procedures
below, depending on the type of installation.
Common Input Connections
4. For common bypass and rectifier inputs, connect the AC input supply cables between the mains
distribution panel and the UPS input (U1-V1-W1-N terminals) and tighten the connections to
5Nm for M6 bolts, to 13Nm for M8 bolts or to 26Nm for M10 bolts. Ensure correct phase rotation.
Split-Bypass Connections
5. If a split-bypass configuration is used, connect the AC input supply cables to the rectifier input
busbars (U1-V1-W1-N terminals) and the AC bypass supply cables to the bypass input
(U3-V3-W3-N terminals) and tighten the connections to 5Nm for M6 bolts, to 13Nm for M8 bolts
or to 26Nm (M10 bolt). Ensure correct phase rotation.
Frequency Converter Mode
If a frequency converter configuration is used, connect the AC input supply cables to the rectifier
input busbars (U1-V1-W1-N terminals). Torque to 5Nm for M6 bolts, to 13Nm for M8 bolts or to
26Nm (M10 bolt). Ensure correct phase rotation. There will not be any AC bypass supply cables to the
bypass input (U3-V3-W3-N terminals) and tighten the connections.
NOTE
The operations described in this section must be performed by authorised electricians or
qualified technical personnel. If you have any difficulties, do not hesitate to contact our
Customer Service and Support Department. See the back page of this manual for contact
information.
NOTE
The earthing and neutral bonding arrangement must be in accordance with local and national
codes of practice.
NOTE
For split-bypass operation, ensure that the linking busbars between bypass and rectifier input
are removed.
The AC input and the AC bypass supplies must be referenced to the same neutral point.
NOTE
For frequency converter operation, ensure that the linking busbars between bypass and rectifier
input are removed.