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NG-IOM-ATT Release 1.2
July 12, 2019
Chapter 1 Materials Required for Installation
The following materials are provided in the NextGen CoolLinks™ HVAC controller package:
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NextGen CoolLinks™ controller enclosure
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Inside temperature sensor with 40 ft. sensor cable
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One, 50 ft. Cat5e Ethernet cables
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Alarm Punch Down Block with pre-wired and pigtail cables
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NextGen CoolLinks™ Installation and Operations Manual (this manual).
The following materials should be provided by the installer:
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Electrical conduit (3/4” and 1”), conduit fittings, mounting straps
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Mechanical installation hand tools (hammer drill, drill bits)
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Label maker & label tags
Chapter 2 NextGen CoolLinks™ Overview
The NextGen CoolLinks™ controller monitors internal and external shelter temperatures and controls the operation of the
Door Mount (DAC) or Wall Mount (WAC) DC Free-Air unit to provide cooling for the shelter equipment. The controller
also operates up to two mechanical-only cooling HVAC units that provide comfort cooling for technicians and serve as a
backup in the event of failure of the DAC/WAC unit. The primary goal of the CoolLinks™ controller is to maximize the
energy efficiency of the environmental control system while maintaining a consistent internal shelter temperature.
2.1 Equipment Architecture
Each telecommunications shelter is equipped with an externally mounted Marvair
®
DAC/WAC DC Free-Air unit and up to
two wall mount mechanical-only cooling HVAC units connected to the NextGen CoolLinks™ controller. A two-line
message display on the front of the controller provides inside and outside temperature and relative humidity indication
together with alarm notification. The controller also includes a Wi-fi hotspot through which technicians can connect with
a smart phone or laptop to determine the status of the system, manually control equipment, review the alarm
information, review and upload event logs, and download software updates.
The DAC/WAC is powered by 48 VDC from the DC plant and consists of a door mount (DAC) or a wall mount (WAC) air
handler unit coupled to an exhaust air damper unit mounted at the opposite end of the shelter from the DAC/WAC. A
CoolLinks™ board inside the DAC/WAC air handler controls an outside air damper and variable speed fan. The exhaust
air damper automatically opens whenever the DAC/WAC variable speed fan is running. When commanded by the
NextGen controller, the DAC/WAC opens its outside air damper and regulates the DC fan speed to introduce outside air
into the shelter to maintain the cooling temperature set point. The NextGen controller communicates over Ethernet to
the DAC/WAC unit.
The mechanical-only cooling DX HVAC units are powered by 208/240 VAC from the shelter Integrated Load Center (ILC).
These units only operate when commanded by a technician to provide temporary comfort cooling, or when the DAC/WAC
is unable to maintain the desired cooling temperature set point, or if the DAC/WAC fails. In addition to cooling, the HVAC
units, if equipped, provide shelter heating. The NextGen controller communicates to the HVAC units via either a
hardwired (thermostat) interface, or over Ethernet if a CoolLinks™ boards is installed in the HVAC unit. The CoolLinks™
interface provides enhanced control features and alarm notification.
