Electrical Service; Nameplate Ratings; Grounding; Voltage Tolerance - Data Aire DAPA-2.5 Installation, Operation & Maintenance Manual

Electrical Service

Before proceeding with the electrical connections, make certain that the volts, hertz, and phase
correspond to that specified on the unit electrical nameplate. Check to be sure the electrical service
provided by the utility company is enough to handle the additional load imposed by this equipment.
Most units with secondary heat exchangers will require a separate power source and field provided
interconnecting wires. See Air cooled condenser and fluid coolers with individual Installation, Operation
and Maintenance Manuals.
Remote condensers will typically require one power source. Glycol systems with fluid coolers and loose
pump(s) typically require one power source for the fluid cooler and will require one additional source
for single pump or two additional sources for dual pumps. Systems where the pump(s) are mounted
and piped integral to the fluid cooler will usually require a single power source.

Nameplate Ratings

Refer to the unit electrical nameplate for equipment electrical requirements. The unit nameplate is
located inside the cabinet on the outside of the electrical control box door. The nameplate includes
Minimum Circuit Ampacity (MCA) also known as wire sizing amps which indicates the minimum
required wire gauge. The Maximum Overcurrent Protection (MOP) device amps indicates the maximum
circuit breaker or fuse size required to protect the system. Max. Fuse or Max. CKT. BKR. indicates the
maximum breaker or fuse size and this information is used to size the appropriate fuses or a Heating,
Air Conditioning, and Refrigeration (HACR) type circuit breaker. Other protection devices are not
allowed based upon the product UL listing.
The facility main distribution panel which provides electrical service to the Data Aire equipment must
be provided with a manual fused disconnect switch or HACR type circuit breaker per local and national
electrical codes.

Grounding

The unit cabinet must have an uninterrupted true earth ground. An electrical ground wire of adequate
size must be connected to the ground lug provided inside the main electrical box.

Voltage Tolerance

Three Phase Voltage Tolerance

The supply voltage to the unit for three phase operation must be within a voltage tolerance per table
below. The maximum allowable voltage phase to phase imbalance must not exceed 3%. Voltage
imbalance causes high amperage over one or several phases, which in turn leads to overheating and
possible damage. The local utility company should be contacted for correction of improper line voltage.
Deviation from ratings can cause premature failures and possibly void unit warranty. For three-phase
units, only three power wires and an earth ground are required. A neutral is not required at the unit
input connections.
NOTICE: Do not mount a customer supplied manual fused disconnect switch
or HACR type circuit breaker to the surface of the unit.
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