Emerson TCDVTM manual General

Guide Specifications

3.0GUIDE SPECIFICATIONS

3.1General

Each condenser shall consist of housing, condenser coil, propeller fans direct-driven by individual fan motors, fan guards, electrical controls and mounting legs. The air-cooled condenser shall have a

_____volt, 3-phase, _____ Hz power supply.

3.2Coil

Liebert manufactured coil shall be constructed of copper tubes in a staggered tube pattern. Tubes are expanded into continuous, corrugated aluminum fins. The fins have full depth fin collars completely covering the copper tubes, which are connected to heavy wall Type "L" headers. Inlet coil connector tubes pass through relieved holes in the tube sheet for maximum resistance to piping strain and vibration. Coils are factory leak-tested at a minimum of 300 psig (2068kPag), dehydrated, then filled with a nitrogen holding charge and sealed for shipment.

3.3Fans

Fans shall have aluminum blades secured to corrosion protected steel hubs. Fans shall be secured to the fan shaft by means of a heavy-duty keyed hub and dual setscrews. Fan diameter shall be 26" (660mm) or less. Fans shall be factory balanced and run before shipment. Fan guards shall be heavy gauge, close-meshed steel wire with corrosion resistant PVC finish that shall be rated to pass a 675-hour salt spray test.

3.4Fan Motors

The variable speed fan motor shall be an inverter duty motor with permanently lubricated ceramic bearings. The Liebert variable frequency drive control system shall provide overload protection for the variable speed motor. Each ambient-temperature-controlled fan motor shall have built-in over- load protection. All motors shall have rain slingers, permanently lubricated bearings and shall be rig- idly mounted on die-formed galvanized steel supports.

3.5Head Pressure Control

The Liebert VFD Condenser control system shall include a variable frequency drive, inverter duty fan motor operating from 0% to 100% motor RPM based on head pressure, refrigerant pressure transduc- ers, ambient-temperature thermostat(s), motor overload protection and electrical control circuit, fac- tory-wired in the control panel. VFD control shall be furnished on the fan adjacent to the connection end of the condenser, which runs continuously with the compressors. Other condenser fans shall be controlled by ambient thermostats and are either On or Off. This system permits operation at temper- atures as low as -20°F (-28.9°C).

3.6Housing

The condenser housing shall be constructed of bright aluminum sheet and divided into individual fan sections by full width baffles. Structural support members, including coil support frame, motor and drive support, are galvanized steel for strength and corrosion resistance. Aluminum legs are provided with rigging holes for hoisting the unit into position.

3.7TVSS and Unit Disconnect Switch

Transient Voltage Surge Suppression and locking disconnect shall be factory-installed and wired in the enclosed condenser electrical panel section.

3.8Alarm Contacts

Normally open, dry contacts shall be provided for indication of VFD and TVSS alarm condition.

3.9Electrical Controls

All electrical connections and controls shall be provided in a weatherproof enclosure. The enclosure shall be integral with the condenser for pleasing appearance as well as functional protection.

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