standards / manuals / guidelines for small hydro development - AHEC

• Check all joints, tightness of bolts and location pins etc. Retighten if necessary.- Stator core winding• Stator tightness of core specially at the top and bottom most packets.• Any local looseness between punchings can be filled up with paramax paper gluedwith epoxy varnish & core bolt retightened.• After repair spray top and bottom three packets with loctite-290.• Clean core duct with dry compressed air• Clean the ends of winding.• Measure IR value of winding after through cleaning; Dry out if IR is low.• Carryout Electronic Core Imperfection detection test also to ensure healthyness ofcore.• After rectifying all defect and thorough cleaning the inner bore and overhang portionof winding is to be spray painted. Paint used should be specified insulating paint.- Maintenance of Rotor• The rotor is to be thoroughly cleaned with dry compressed air.• Check general condition of coil and pole, clean with dry compressed air.• Check the coil joints for any cracks due to overheating etc.• Check field coils and rotor leads for inter turn fault. Measure impedance of coils byapplying 60 to 100 VAC, 50 C/s If impedance of some coil is very low (