Old transfo from Burroughs computer of the 70's

alpibucky schrieb:

Hi,

This could be a

Constant voltage transformer

By arranging particular magnetic properties of a transformer core, and installing a ferro-resonant tank circuit (a capacitor and an additional winding), a transformer can be arranged to automatically keep the secondary winding voltage relatively constant for varying primary supply without additional circuitry or manual adjustment. Ferro-resonant transformers run hotter than standard power transformers, because regulating action depends on core saturation, which reduces efficiency. The output waveform is heavily distorted unless careful measures are taken to prevent this. Saturating transformers provide a simple rugged method to stabilize an AC power supply.

You'll find additional information here (chapter 4.9, picture 4.6.1, p. T32):

HTH

Reinhard

The HV capacitor makes it sound like ferrorresonant power supply.

I can't explain exactly how they work, but they output a magnetically regulated output voltage. Line input variations will not affect the output. In fact on some of these you can input square waves and the output remains a nice sine wave.

Their efficiency is poor, but they are simple and extremely reliable.

That might be true. You might have something like this (view in a fixed width font):

3 ----) )

1-2 and 4-5 are probably designed for 100 V or 105 V, and 1-3 and 4-6 are probably designed for 115 V or 120 V. If you link 3 and 4, then you can apply 230 V or 240 V mains power to 1 and 6. (With no link on 3 and

Get another power transformer of known characteristics, like 230 V : 6 V or 230 V : 12 V. Output of 1 or 2 A is probably more than enough. Connect the 230 V side of this transformer (carefully) to mains power, and then connect the 6 V or 12 V output of this transformer to the main input of your Burroughs transformer. Measure the 6 V or 12 V output of your known transformer, and then (carefully) measure the other outputs of the Burroughs transformer. From that, you can determine the voltage ratios of all the windings of the Burroughs transformer. Leave the capacitor connected to the Burroughs transformer for this.

To figure out the power (W) ratings of each output, you can measure the voltage with no load, then load down each output with something (resistors, incandescent lamps) until the voltage drops 10%. The current (A) at that point is probably pretty close to the current rating of that output.

Read all of the following

I hope this helps!

Matt Roberds