A Fläkt Woods Company 2933 Symmes Road, Fairfield, Ohio 45014-2035 Phone: (513) 874-2400 Fax: (513) 870-6249 JM AEROFOIL FANS Installation, Operation and Maintenance Instructions Site Storage The fan must be stored in clean, dry conditions in a vibration-free area. Before installation, the resistance to ground should be measured. If this is less than 1 mega ohm the motor should be dried out before applying main voltage. The impeller should be rotated monthly (minimum) to prevent hardening of the grease and corrosion of the bearings. Supply The details of the site supply must be checked to ensure that the voltage, frequency, power rating and number of phases comply with the details given on the motor nameplate. Installation The Aerofoil fan is supplied completely assembled and is tested at the factory. Weatherproof motors are provided with drain holes and in humid or wet conditions, must be mounted with the drain holes at the lowest point. If the drain holes are plugged the plugs must be removed before commissioning. When installing the fan, sharp bends in the ductwork should be avoided in the vicinity of the fan. For optimum performance, the connection to the ductwork should be by means of a smooth transformation duct with a 60 maximum effective included angle when the diameter decreases in the direction of the airflow, or a 15 maximum effective included angle when it increases in the direction of the airflow. The height of the fan supports should be adjusted so that no undue distortion of the fan casing or mounting occurs. When vibration isolators are used, flexible connectors and electrical conduit should also be used. The flexible connectors should be fitted so that they are almost taut and completely overlap the spigot on the matching flange. The fan should be aligned closely with the inlet and outlet ductwork and must be fitted in accordance with the airflow direction and rotation arrows shown on the nameplate. Typical installations are shown on figures 1 and 2. When installing multi-stage fans, refer to duct nameplate for stage number, stage 1 is installed in the upstream position, and comply with airflow direction and rotation arrows. Aerofoil bifurcated fans when mounted horizontally should have the motor inlet/outlet tunnel positioned at 3 o clock, 9 o clock or vertically downwards (not upwards). Page 1 of 12
Connection The wiring must be connected in accordance with the wiring diagram in the terminal box. The direction of rotation is marked on the casing to comply with the form of running required. Single-phase motors are shipped correctly connected. Three phase motors require a trial connection to the supply; if the rotation is incorrect, interchange any two phases of the three-phase supply. Warning - Disconnect and lock out electrical supply before servicing. Failure to do so may result in injury or death. Grounding The fan must be grounded in accordance with the requirements of the local supply authority or code of practice. A separate ground continuity conductor should be connected to the grounding screw in the terminal box. Conduit Wiring should be in accordance with the local regulations and code of practice. For explosion proof motors, see separate section. Balance and Vibration All fan impellers are dynamically balanced prior to installation in the fan assembly. After assembly, fans supplied with motors are test run and fine-tune balanced to reduce vibration levels to acceptable limits as shown in table below (from AMCA Standard 204-96). After field installation, fans will need to be checked prior to commissioning, to assure that the vibration levels do not change significantly from those achieved at the factory. It is recommended that the velocity values in the table below are not exceeded by more than 10% when field installed. Fan Application Category Rigid Mounted Flexible Mounted mm/sec. (in./sec.) mm/sec. (in./sec.) BV-3 3.8 (0.15) 5.1 (0.20) The installed vibration level of any fan is not solely dependent on the balance grade. Installation factors such as the mass and stiffness of the supporting system, will influence the as installed vibration level (Refer to AMCA Publication 202, Troubleshooting). Therefore, the as installed fan vibration level is not the responsibility of the fan manufacturer unless specified in the purchase contract. Page 2 of 12
Starting Starting of the fan may be carried out manually or automatically. The number of starts in a given time should be limited as follows: 4 direct on line starts/ hour 2 reversals per hour with a run-down time of 15 seconds before reversal 2 starts in quick succession followed by 30 minutes cooling, which may be achieved either by running or switching off Protection Any fuses in the circuit should be regarded as protecting the wiring against the effects of short circuits or ground faults only. They are not suitable for overload protection. To provide protection against a blown fuse or a bad contact, a starter with single phasing protection should be used. The overload current setting should be up to 1.15 times the nameplate current. Motors fitted with thermistor or thermostatic overheat protection should be wired in accordance with the instructions given. Operating Conditions Standard fans are suitable for use in an ambient temperature of -40 C to +40 C, except for the belt driven fans that may be used up from 0 to 80 C, provided the motor is in ambient from -20 to 40 C. The maximum ambient temperature in which an individual fan may be used is given on the nameplate. When fans are operating in ambient temperatures below 0 C icing up must be avoided. Standard fans are not suitable for handling air containing free moisture or corrosive fumes. Routine Maintenance After three months, and thereafter as experience dictates, the fan should be inspected to ensure that there is no build-up of dirt or other matter that would cause overheating of the motor or obstruct the impeller track. The belt tension of Belt Driven Aerofoils should be checked after the first few hours running and thereafter at 3 monthly intervals or as experience dictates. Lubrication The fan is supplied lubricated at the factory and should be lubricated periodically per instructions affixed to the fan. Motors with Lubricators and Bearing Housings Details of the relubrication period and the quantity of lubricant are given on Figures 5 and 6. When carrying out relubrication it is essential that every trace of dirt and water is removed from around the grease nipple and that a clean grease gun is used. Only a low pressure should be required to inject the specified quality. If a high pressure is required the cause should be investigated. Page 3 of 12
Additional Instructions for Explosion Proof Motors Explosion proof motors must only be wired by qualified electricians familiar with all local and national codes for wiring of explosion proof motors. Joints should be made though special explosion proof junction boxes or unions throughout the hazardous area. At a point outside the hazardous area, the explosion proof conduit system must be sealed off by a special junction box having an explosion proof barrier. Glands and flexible cable should be used to connect to the fan when it is supported on resilient mountings. Operating Conditions Provided the motor is not allowed to become coated with dirt, dust, or other solid matter that would restrict surface cooling, the carcass temperature will never exceed 80 C when operating in the maximum ambient temperature of 40 C. It is incumbent on users to satisfy themselves that this carcass temperature is safe under the conditions of use and with respect to the particular flammable media in the vicinity. Warning: Failure to comply with these instructions may result in injury or death. Safety When installing or using products the following precautions must be taken. 1. No work may be carried out without switching off and locking out the electrical supply. 2. If it is necessary to carry out any assembly operations before installing the fan, ensure that all fasteners are tightened securely and that any lifting points provided are used. 3. The security of fasteners and the integrity of components should be checked regularly as part of the routine maintenance operation. Particular attention should be paid to impeller fastening screw. 4. Do not re-use locking devices such as lock washers or wedge-lock screws. 5. If the unit is installed where there is a reasonable possibility of persons or objects coming into contact with the impeller, a guard must be fitted. It is the responsibility of the installer and the user to ensure that the installation complies with all OSHA regulations. Where a unit is installed so that a failure of components could result in injury to personnel, precautions should be taken to prevent such an injury. Motor Maintenance Lubricate motor bearings to the manufacturer s recommendations. Lubrication recommendations are included with the packet attached to the fan. Should this packet be missing, the following will apply: Page 4 of 12
A. Fractional Horsepower Sleeve Bearing Motors: Under normal operation at ordinary temperatures and clean surroundings, these motors will operate for three years without re-lubrication. Then lubricate annually with electric motor oil or SAE 10 oil. Under continuous operation higher temperatures (but not to exceed 104 F ambient) re-lubricate annually. B. Fractional Horsepower Ball Bearing Motors: Under normal conditions, ball bearing motors will operate for five years without relubrication. Under continuous operation at higher temperatures, (but not to exceed 104 F ambient) re-lubricate after one year. To re-lubricate where motors are not equipped with pressure fittings, disassemble motor and clean the bearings thoroughly. Repack each bearing one-third full with ball bearing grease. C. Integral Horsepower Ball Bearings Motors: Motors having pipe plugs or grease fittings should be re-lubricated while warm and at standstill. Replace one pipe plug on each end shield with grease fitting. Remove other plug for grease relief. On low pressure, grease, run and lubricate until new grease appears at grease relief. Allow motor to run for ten minutes to expel excess grease. Replace pipe plugs. Motors not having pipe plugs or grease fittings can be re-lubricated by removing end shield, cleaning grease cavity and refilling three-fourths or circumference of cavity. Recommended re-lubrication intervals (General guide only) H.P Standard Duty Severe Duty Extreme Duty Range 8 Hr./Day 25 Hr./Day Very Dirty Dirty-Dusty High Ambients 1 ½ - 7 ½ 5 Yrs. 3Yrs. 9 Mos. 10 40 3 Yrs. 1 Yr. 4 Mos. 50 150 1 Yr. 9 Mos. 4 Mos. Recommended Motor Greases Polyrex EM Exxon Oil Company SRI #2 Chevron Oil Company FAN MOTORS USED WITH VARIABLE FREQUENCY DRIVES 1. Specify Inverter Duty Motors whenever possible. If this is not practical, premium efficiency motors must be specified. 2. Specify motors with inverter spike resistant magnet wire when possible. 3. Specify insulated bearings or provide shaft grounding to prevent shaft currents from causing bearing damage and premature failure. This is critical on motors that are 50 HP and larger since the cost of downtime and bearing replacement is typically much greater on larger motors, than the initial cost of one of these preventative measures. Note: Shaft currents can occur on any motor HP rating when used with a variable frequency drive. 4. Specify the same manufacturer for both the motor and variable frequency drive, if possible, for single-source responsibility. Page 5 of 12
5. A load reactor should be installed in series in the power leads between the VFD and the motor, located as closely as possible to the VFD. This is an inexpensive preventative measure, especially if the VFD is more than 75 feet from the motor. 6. The switching frequency of the IGBT s in the VFD should be kept as low as practical to prevent higher temperatures in the motor and the VFD. However, lower switching frequencies cause higher noise levels in the motor. Therefore, the application noise level versus the higher temperature must be carefully weighed. Generally, 2.5 Khz is optimal. 7. Good industrial wiring practices, including proper grounding, that meet local and national electric codes must be followed. 8. It is best to limit the minimum frequency to the motor to 10 Hz or more for extended periods of time. Note: These are general recommendations only. As each application is different, you must consult the motor and drive manufacturer for specific requirements as they apply to your installation. WARNING! Shaft currents are phenomena created by the interaction between motors and variable frequency drives that can cause premature motor bearing failures. The occurrence of shaft currents is common and cannot be predicted. American Fan Company has experienced many motor bearing failures that have been positively identified as 'shaft current' problems due to the distinctive failure pattern seen in the failed bearings. American Fan Company recommends the adoption of the above list of design constraints for any fan/motor/vfd combination. Regardless if any or all precautions are taken, American Fan Company accepts no responsibility for shaft current related motor bearing failures and will extend only the warranties of the motor and/or variable frequency drive manufacturer (when supplied by American Fan Company). Further, American Fan Company will not be held liable for any consequential damages under any circumstances resulting from premature bearing failures due to shaft currents. V-Belt Drive Maintenance If belts squeal at start-up, they are too loose and should be tightened. Periodically check belt and sheave wear, alignment, and tension. When belts show wear, replace all belts at once with a new matched set of belts. New belts will not work properly in conjunction with used belts due to difference in length. Belts and sheaves should be clean and free from grease. After installing new belts, check tension midway between sheaves. Belts should deflect about 1/64 per inch of span length with approx. 20-lb. force. Allow unit to run for 4 6 hours, then it will be necessary to re-tighten belts again because new belts tend to stretch initially. Vibration Level of Replacement Impellers All replacement impellers are dynamically balanced at our factory prior to shipment. Occasionally, an impeller that has been factory-balanced will yield poor balance/vibration results when installed and operated. This does not mean that the impeller was incorrectly Page 6 of 12
balanced at the factory. It can result from differences between test-stand conditions and operating conditions. A factory test stand has different bearings, bearing spans, structural response, stiffness, mechanical impedance, and by necessity, running speed. The test stand cannot duplicate the actual fan system and its response. For these reasons, the fan system vibration levels must be checked after installing a replacement impeller. Refer to page 4 for acceptable vibration levels. NOTE: All illustrations used in this Operation Manual are for Reference Only. Contact your local American Fan Representative if further assistance is needed. ORDERING SPARE PARTS Service and Parts: Phone: (513) 874-2400, Dial 2 Fax: (513) 870-6249 E-mail: greg.robinson@flaktwoods.com Page 7 of 12
Contact the local American Fan Co. sales representative or AFC Service and Parts Department and supply the following information: 1. Fan serial number stamped on nameplate. 2. Fan code and model stamped on nameplate. 3. Fan arrangement. 4. Description of part required. 5. Part number if part is a casting. 6. Special materials, paints or coatings. WHEEL Be sure to indicate direction of rotation as viewed from drive side, type of wheel and the operating speed. SHAFT Length and diameter. MOTORS The name of the motor manufacturer, motor model number, and serial number from the motor nameplate must be supplied to the factory for repairs or replacement. BEARINGS The following information should be indicated when ordering various types of bearings: ANTI-FRICTION BEARINGS 1. State whether ball or roller. 2. Manufacturer. 3. Size and number. 4. Fixed or floating. RECOMMENDED SPARES: 1. V-belts on V-belt driven fans. 2. Fan bearings 3. Wheel (s) 4. Motor (if blower is critical to your operation). Page 8 of 12
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AMERICAN FAN COMPANY TERMS OF SALE AND WARRANTY For details, please contact factory: American Fan Company 2933 Symmes Road Fairfield, OH 45014 Phone: (513) 874-2400 Fax: (513) 870-6249 Page 12 of 12