Testing Standards
 
  Standards Followed for Quality Assurance Process
  Stator Coils and Completed Winding :
 
INSULATION RESISTANCE TEST EQUIPMENT RATED LINE TO LINE VOLTAGE
U = < 1 K V 1 - 2.5 KV 3 - 5 KV 6 - 12 KV > 12
All the coils / bars / completed winding before and after HV test (IEEE 95 - 1977) 500 V 500 - 1000 V 1000 - 2500 V 2500 - 5000 V 5000 - 10,000V
POLARISATION INDEX TEST (PI) EQUIPMENT RATED LINE TO LINE VOLTAGE
U = < 1 K V 1 - 2.5 KV 3 - 5 KV 6 - 12 KV > 12
All the coils / bars / completed winding ( IEEE Stds. 43 Sec. 5.4, 9.2 & 12.2 ) 500 V 500 - 1000 V 1000 - 2500 V 2500 - 5000 V 5000 - 10,000V
INTER LAMINAR INSULATION TEST Detected by Flux Loop or Core Tester (ELCID)
All the core pack of AC induction motor, Generators & DC Armature (IEEE Stds. 435 Sec. 9.1)
SUB CONDUCTOR TEST  
All formed multi conductor stator coils / bars are tested before pre stack (CORAL Practice) Conductor to Conductor 1000 Volts. AC
All formed multi conductor stator coils / bars are tested after pre stack (CORAL Practice) Conductor to Conductor 500 Volts. AC
All formed multi conductor stator coils / bars are tested after moulding (ESI 44-7 - 1978) Conductor to Conductor 110 Volts. AC
 
 
Routine Test Standards Followed Machine System Voltage ( U ) and Test Voltage in KV
HV TEST 3.3 6.6 11 13.2
AC HV test on newly formed coils / bars in our works
at 1.3 (2 U + 1) (IEC 60034/BS 4999 & 5000)
10 18 30 36
AC HV test after positioning and wedging the coils / bars in the slots at (2 U + 3) (CORAL Practice) 10 16 25 29
AC HV test on completed stator winding after group forming before making internal (or) D (2U + 2) (CORAL Practice)

9 15 24 28
AC High Voltage test in front of the customer (2U + 1) 7.6 14.2 23 27.5
SURGE COMPARISION TEST  
After spreading the individual coil (1.5 U + 1) (CORAL Practice) 6 11 17.5 NA
After pre stacking the individual coils (1.5 U ) (CORAL Practice) 5 10 16.5 NA
After completing full moulding individual coils (1.5 U) ) (CORAL Practice) 5 10 16.5 NA
Complete stator winding (2U + 1) (EASA AR 100-2001) 8 15 23 NA
HIGH VOLTAGE HIGH FREQUENCY TEST (Turn To Turn Test for Multi Turn Formed Coils)  
4.5 9 15.5 18.6
4.5 9 15.5 18.6
 
 
TAN DELTA TEST  
All the stator coils / completed stator winding (IEEE Stds. 432, Sec.8.1) At 0.2 U, 0.4 U, 0.6 U, 0.8 U & 1.0 U
DIMENSIONAL CHECKING  
After completing entire moulding (ESI 44-7 - 1978) All the coils / bars
 
  Residual Life Assessment Test (RLA)
 
 
Test Part Standards Follow
Winding Resistance Test Stator, Rotor and Exciter Parts BS 4999 Part 60 : 1976
Insulation Resistance Test Stator, Rotor and Exciter Parts IEEE 95 - 1977
Polarisation Induction Test (PI) Stator, Rotor and Exciter Parts IEEE Stds. 43 Sec. 5.4, 9.2 & 12.2
Hi-Pot Test
(Dielectric Absorption Test)
Stator, Rotor and Exciter Parts IEC 34 - 18 - 33
IEEE Stds. 432 - 1992
Inter Lamination Test High Voltage AC Stator winding IEEE Stds. 435 Sec. 9.1
Tan Delta Test High Voltage AC Stator winding IEEE Stds. 432, Sec.8.1
Inter Turn Insulation Test
(Surge Comparison)
Stator, Rotor and Exciter Parts EASA AR 100-2001
Recurrent Surge Oscillosgraph
(RSO) Test
Cylindrical Rotor IEEE Stds. 432 - 1992
Rotor Winding Impedance Test Cylindrical / Salient Pole / Cruciform Rotors IEEE Stds. 432 - 1992
Wedge Tightness Test Stator and Rotor IEEE Stds. 432 - 1992
Slot Discharge and Corona Probe Test High Voltage Stator IEEE Stds. 432 - 1992
Step Voltage Test High Voltage Stator IEEE 95 - 1977
Visual Inspection All Electrical & Mechanical Parts IEEE Stds. 432 - 1992