I am finishing my 5 channel class a/b power amp. I need to power 3 p33 speaker protection boards from Rod Elliot. Now I will be using a 24vdc separate transformer. Should the centre tap be tied to the ground of the boards? Main star ground? Or should be left alone and the ground from the main transformer be used for the ground for the boards? The ac in and dc in will be connected from the separate transformer.
Please post a diagram of your intended wiring scheme. That would give the best chance of us helping your arrive at the best answer.
Ms paint is fine. A picture is worth a 1000 words as the saying goes.
Ms paint is fine. A picture is worth a 1000 words as the saying goes.
I will try and draw a picture. Basically, I want to add a second transformer in my amp. This second small transformer would just power the speaker protection and relay boards. It has a centre tap. Do I tie it to my main transformer star ground? I would be taking 1 ac leg and 1 dc + leg from the bridge rectifier for the second transformer to power my boards.
I can't follow your description sorry. I would really need a diagram to clearly understand what you are proposing.
Even a scribble with pencil and paper would work.
On a side note, why not use your transformers that is powering your amp board. That is how the p33 is normally used. Saves on cost snd complexity.
Even a scribble with pencil and paper would work.
On a side note, why not use your transformers that is powering your amp board. That is how the p33 is normally used. Saves on cost snd complexity.
The ground on p33 module needs to be connected to the 0v at the output of the psu supplying it.
Assuming the secondary power transformer is 12v-0v-12v. You would be better to just use the outer taps and ignore the centre tap to make a 35vdc power supply to power the p33 as this is its native setting.
You could make a circa 18vdc power supply be using just the centre tap on the transformer and one of the outside taps.
You can run it on a 18vdc but this requires some change of resistor values which are explained by Rod on the paid side of his website.
Assuming the secondary power transformer is 12v-0v-12v. You would be better to just use the outer taps and ignore the centre tap to make a 35vdc power supply to power the p33 as this is its native setting.
You could make a circa 18vdc power supply be using just the centre tap on the transformer and one of the outside taps.
You can run it on a 18vdc but this requires some change of resistor values which are explained by Rod on the paid side of his website.