Whats the max voltage my cars electrical system will generate?

[Perry Babin]

The secondary may be completely isolated from the primary. When you measure the voltage on the secondary, you need to use the secondary center tap as the reference (black meter lead in sec center tap).

Using the secondary center tap as the reference, do the pulses on the outer legs of the rectifiers maintain the same amplitude when you connect the fan?

[MikeHunt79]

Originally posted by Perry Babin
The secondary may be completely isolated from the primary. When you measure the voltage on the secondary, you need to use the secondary center tap as the reference (black meter lead in sec center tap).

Using the secondary center tap as the reference, do the pulses on the outer legs of the rectifiers maintain the same amplitude when you connect the fan?

Damn, I totally forgot about the grounds being isolated... I was using the ground on the input all along.

The blob of solder in the middle of the output caps is actually the secondary ground. So I simply wired the fan up to secondary ground instead of the primary ground, and it starting whizzing away at 26v.

This was definitely a eureka moment for me, thank you! I can now get around to squeezing the amp9 into the amp case.