Hello all. I am trying to fix one of my problematic Apple Lisa PSU 120 VAC, 60 Hz, 1.2 Amp, 150W which isn't working.
First thing that came to my notice is a resistance of the Transformer (T2 in the attached schema).
I have compared it with the other working PSU 1.2 AMP but dedicated for 220-240 V~, 50 Hz, .7 A, 150 W.
I have measured the resistance with multimeter between 2 and 5 pins and it shows OL (open line).
On the working one ( 220V version PSU) it shows 1k Ohm. So it looks very suspicious for me.
The question is: Is it normal for 120VAC version? Can anyone help me to confirm and measure their T2 resistance values (between pin 2-5) ? I am especially interested in 120VAC Transformer version measurements.
I have also noticed difference in serial number of T2 transformer for 120VAC version and for 220V version.
120VAC version has EXCEL Transformer with number 157-0015-A. 220-240 V~ version has EXCEL Transformmer 157-0016. So this might have an impact?
I am atttaching pictures of my suspicious T2 from Apple Lisa PSU 120 VAC, 60 Hz, 1.2 Amp, 150W.
Thank you
First thing that came to my notice is a resistance of the Transformer (T2 in the attached schema).
I have compared it with the other working PSU 1.2 AMP but dedicated for 220-240 V~, 50 Hz, .7 A, 150 W.
I have measured the resistance with multimeter between 2 and 5 pins and it shows OL (open line).
On the working one ( 220V version PSU) it shows 1k Ohm. So it looks very suspicious for me.
The question is: Is it normal for 120VAC version? Can anyone help me to confirm and measure their T2 resistance values (between pin 2-5) ? I am especially interested in 120VAC Transformer version measurements.
I have also noticed difference in serial number of T2 transformer for 120VAC version and for 220V version.
120VAC version has EXCEL Transformer with number 157-0015-A. 220-240 V~ version has EXCEL Transformmer 157-0016. So this might have an impact?
I am atttaching pictures of my suspicious T2 from Apple Lisa PSU 120 VAC, 60 Hz, 1.2 Amp, 150W.
Thank you
