i have a customer who has an old generac genset. i was troubleshooting it and i recommended a replacement of avr. since the availability of that avr (part #: 67680) is low here in our country, i tried using a stamford avr which is the sx460.
with respect to the wires/terminals on the alternator, the sx460 avr is compatible to use. i got the generac alternator model and serial numbers and i tried looking for it on the internet. it was very difficult to find since it is already an obsolete one, i think. here is the model and serial number:
alternator m/n: 95a01530-s
alternator s/n: 2019651
i had already installed the sx460 avr and i test run the genset to set the voltage but the voltage won't build up. i looked at the manual of the sx460 avr and it requires a >4vac residual voltage. i checked the voltage at the terminals and it was very low, only at 0.916vac which the avr cannot build up. i already did field flashing for 3-5 seconds but the residual voltage still won't rise to >4vac.
i also tried exciting the field through the 12vdc battery of the engine, while running at no load, and the voltage at the terminal rose to more than 250vac which, i think, means that the exciter field is okay but my problem is that the residual voltage is too low for the sx460 avr. even field flashing cannot rise the residual voltage to >4vac.
i'm just asking what could be the problem of the alternator. the alternator seems to be brushless as to what i had seen. and it had only 2 lead wires and it has an exciter rotor and field. i am already considering recommending pulling out the whole alternator and rebake it to increase the insulation of the alternator which could help rise the residual voltage of the alternator according to my previous experience. but this would also mean an increase to the cost of the project which is not expected by the customer. that is why i tried asking here first before doing that.
sorry for the very long story. it is my first here and i'm just asking for advice. thanks for any reply.
with respect to the wires/terminals on the alternator, the sx460 avr is compatible to use. i got the generac alternator model and serial numbers and i tried looking for it on the internet. it was very difficult to find since it is already an obsolete one, i think. here is the model and serial number:
alternator m/n: 95a01530-s
alternator s/n: 2019651
i had already installed the sx460 avr and i test run the genset to set the voltage but the voltage won't build up. i looked at the manual of the sx460 avr and it requires a >4vac residual voltage. i checked the voltage at the terminals and it was very low, only at 0.916vac which the avr cannot build up. i already did field flashing for 3-5 seconds but the residual voltage still won't rise to >4vac.
i also tried exciting the field through the 12vdc battery of the engine, while running at no load, and the voltage at the terminal rose to more than 250vac which, i think, means that the exciter field is okay but my problem is that the residual voltage is too low for the sx460 avr. even field flashing cannot rise the residual voltage to >4vac.
i'm just asking what could be the problem of the alternator. the alternator seems to be brushless as to what i had seen. and it had only 2 lead wires and it has an exciter rotor and field. i am already considering recommending pulling out the whole alternator and rebake it to increase the insulation of the alternator which could help rise the residual voltage of the alternator according to my previous experience. but this would also mean an increase to the cost of the project which is not expected by the customer. that is why i tried asking here first before doing that.
sorry for the very long story. it is my first here and i'm just asking for advice. thanks for any reply.
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