Electrical Installation
Vertiv | Liebert CRD10 | User Manual
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Chapter 4: Electrical Installation
In this chapter, the electrical installation of the CRD10 air cooled units is explained in-depth to help users
with the various tasks that include the cable connections of the indoor unit apart from the checklist. The air
conditioners of the Liebert CRD10 models are the professional devices used in industrial, commercial, or
other professional occasions. It is not tailored for the general public.
A port of greater than a 350 short-
circuit-ratio is required between the user power and the grid. Permission is required from the power supply
department to ensure that the air conditioner is connected to a power greater than 350 short-circuit-ratio.
WARNING! Arc flash and electric shock hazard. Open all local and remote electric power-supply
disconnect switches, verify with a voltmeter that power is Off and wear appropriate, OSHA-approved
personal protective equipment (PPE) per NFPA 70E before working within the electric control
enclosure. Failure to comply can cause serious injury or death. Customer must provide earth ground
to unit, per NEC, CEC and local codes, as applicable. Before proceeding with installation, read all
instructions, verify that all the parts are included and check the nameplate to be sure the voltage
matches available utility power. The Liebert® controller does not isolate power from the unit, even in
the “Unit Off” mode. Some internal
components require and receiv
e power even during the “Unit Off”
mode of the controller. The only way to ensure that there is NO voltage inside the unit is to install and
open a remote disconnect switch. Refer to unit electrical schematic. Follow all local codes.
WARNING! Risk of improper wire sizing/rating and loose electrical connections. Can cause overheated
wire and electrical connection terminals resulting in smoke, fire, equipment and building damage,
injury or death. Use correctly sized copper wire only and verify that all electrical connections are tight
before turning power On. Check all electrical connections periodically and tighten as necessary.
NOTICE!
Risk of improper power-supply connection. Can cause equipment damage and loss of warranty
coverage.
Prior to connecting any equipment to a main or alternate power source (for example: back-up
generator systems) for start-up, commissioning, testing, or normal operation, ensure that these
sources are correctly adjusted to the nameplate voltage and frequency of all equipment to be
connected. In general, power-source voltages should be stabilized and regulated to within ±10% of the
load nameplate nominal voltage. Also, ensure that no three-phase sources are single-phased at any
time.
4.1
Installation Notes
1.
The connections of all power cables, control cables, and ground cables should be in compliance with the
local and national electrical regulations.
2.
Observe the unit nameplate for the full load current. The cables sizes must meet the conditions as
specified in the local wiring protocols and rules.
3.
The power supply of the unit must be consistent with the power supply specifications of the nameplate,
otherwise the unit will be damaged. Mains supply requirement:
