A.General
The electronic air cleaner shall be the two stage, dual voltage, plate type electrostatic precipitator, sized to clean the airflow capacities scheduled on the Contract Documents at an efficiency of at least (specify %) as determined by the ASHRAE Standard 52.1-92, Dust Spot Test Method. Air cleaner shall be furnished with built-in high pres- sure, low volume water/detergent washing system and programmable logic control for complete auto- matic operation.
B.Configuration (Select B.1or B.2)
B.1 The electronic air cleaner shall be furnished in a side access housing, fabricated from 16 gage gal- vanealed steel, continuously welded, primed and painted. The housing shall be furnished with gas- keted, hinged access door with safety electrical interlock, flanged inlet/outlet collars, built-in clean- ing system and sloped bottom drain pan. The housing shall be tracked for and furnished with alu- minum pre and post mist eliminators and ionizing- collecting cells.
B.2 The electronic air cleaner shall be front/rear access, furnished using prefabricated, galvanized framework designed to contain ionizing-collecting cells and wash system. All frame sub-assemblies shall be match marked and prepared for bolted field assembly. Base support framework shall be stainless steel. All necessary fasteners and fittings shall be furnished. Framing shall be designed for cell removal either upstream or downstream and pre-punched air by-pass baffles shall be provided for the upstream side. The foundation supporting the framework, including drains and specified opening shall be prepared by the Contractor in accordance with the manufacturer's recommenda- tion and written instructions.
C.Electronic Collector Modules
Ionizing-collecting cells shall be of industrial design integrity and single unit construction. The cells shall be all aluminum construction except the ioniz- ing electrode shall be of the rigid stainless steel type without serrated spikes or the tungsten wire type. Repelling and collecting plates shall be pos- itively retained in place using tie rod and tubular spacer design. High voltage insulators shall be molded from structural, self-glazing ceramic; shall contain no appurtenances; shall be of radial and bilateral symmetry; shall contain no high voltage penetrations and shall not contact the high voltage on the process air side. The entire assembly shall be suitable for handling cold saturated air.
D.Built-in Cleaning System
Water/detergent washing system shall be high pressure, low volume type. Detergent, wash and rinse water shall be applied by oscillating copper
manifolds containing brass spray nozzles, located on both the air entering and air leaving side of each module tier. Complete, effective washing of all ion- izing-collector cell surfaces and all appurtenances shall be provided. Drive motors, used to oscillate the manifolds, shall be high torque, gear reduced, totally enclosed fan cooled type, and be perma- nently lubricated. Drive linkage shall be a rigid, positively fastened type without tracks or sprock- ets.
One detergent dispensing assembly shall be pro- vided to serve each electronic air cleaner. The detergent dispenser shall consist of a (specify 30 or 55) gallon anti-corrosive reservoir, positive dis- placement pump, motor, and flow volume control valve.
Solenoid valve, strainer, backflow preventer, ball valve, and an initial supply of detergent shall be fur- nished by the electronic air cleaner manufacturer.
E. Control and High Voltage Power Supplies
Each electronic air cleaner shall use a single remote-mounted control and power supply, con- tained in NEMA 12 enclosures. The unit shall oper- ate on 120 Vac, 1Ph, 60 Hz.
The control shall be of the programmable logic (PLC) type, furnished in a NEMA 12 enclosure, preprogrammed to sequence the electronic air cleaner through wash cycles at a schedule to be determined with the Owner. Integral electronic time clock with manual override shall be provided.
High voltage power supply, furnished in a NEMA 12 enclosure, shall be the high frequency, solid state type, supplying a dual voltage and current output specified by the electronic air cleaner manufactur- er. Power supply shall have a regulated input and output for line fluctuations of 10% and shall have a current limiting shutdown and restart feature.
The face panel of the enclosures shall contain indi- cators for electronic air cleaner control status (run, wash, etc.), individual power supply, primary circuit indicating light, monitoring instrumentation, and on- off switch.
Provide enable/disable contacts suitable for inter- face with the specified Building Control and Management System (BMS).
F. Electrical Interlocks
Furnish duct door electrical interlocks, disconnect switch, and pilot light assembly. All access to elec- tronic air cleaners and high voltage power packs shall contain electrical safety interlocks which de- energize the primary power circuit prior to access- ing high voltage.
