[jules]

I have a 1,000VA transformer that is supposed to supply AC power to a PSU for an output board and also to a gain board. This is a diagram showing the taps available on the transformer and the connection points on the two boards:





The wiring shown in red was provided by my esteemed adviser but it seems to leave me with no symmetrical way to wire the gain board given the taps I've got left are 0-24V and 0-9V in a situation where there are 3 connection points on the gain board [see lower right of diagram].

Am I missing something here or do I have the wrong transformer for the job?

jules 

[chlorofille]

Hi,

What is the required voltage for operation of the gain board?

[jules]

Hi chlorophille:

this is the gain board with the AC inputs elipsed:





As I understand it 32V is about right but it appears to me that a 0-33V wouldn't do the job since there's a centre [0 volt I guess] connection on the board.

jules

[chlorofille]

Hi,

I am straining to see but I think I can make out a 32-0-32V represented by the blue and green tap. You need to connect the output of the power supply board to the input of the gain board. The nature in which the blue and green taps are connected already produce a symmetrical power supply, suitable for the gain board. Judging from the power supply caps and diodes on the gain board, it will accept AC input voltage. Double check your power supply board and verify that it outputs AC, not DC.

The yellow and black transformer taps will not be used in this instance.
You can leave those taps unused(unloaded), but insulate the exposed leads thorougly to pevent shorts.

[jules]

Thanks Chlorophille,

Sorry, I should have made those figures larger but yes, the outputs are, top to bottom 0-32V, 0-32V, 0-24V, 0-9V.

The inputs to the PS board and the gain board are both definitely AC.

The design requires separate output circuits for each board. Further discussion with my adviser leaves the slight possibility that the 0-9V has been incorrectly labeled and could be 0-24V. I'll check tonight though I'm not all that hopeful.

jules