Full wave vs full wave bridge rectifier?

[lightfoot]

When designing the power supply for a power transformer with no high-voltage center tap when should a full wave rectifier with no artificial center tap be used and when should a full wave bridge rectifier be used with an artificial center tap?

Thanks

[gktamps]

It might help you to look at the answer to your question graphically. I specified the following search terms to capture both full wave and full bridge rectifiers. See if this helps, then go from there.

https://www.google.com/search?q=full+re ... 1051US1053

[lightfoot]

It might help you to look at the answer to your question graphically. I specified the following search terms to capture both full wave and full bridge rectifiers. See if this helps, then go from there.

https://www.google.com/search?q=full+re ... 1051US1053

A good example of a full wave rectifier can be found on the schematic of a Fender Blues Deluxe. There’s no artificial center tap.

[lightfoot]

I think the question I’m actually trying to present is under what circumstance would you not want to use an artificial center tap as part of the rectifier?

[pompeiisneaks]

I think the question I’m actually trying to present is under what circumstance would you not want to use an artificial center tap as part of the rectifier?

There are probably other considerations, but the biggest being full wave converts AC into about 0.9 DC, or about 90% of the input power is DC. Full Wave Bridged instead puts out 1.4 times the input AC. 140% So the gist of the decision is usually linked to:

1. what power transformer do I have, and what is it's unrectified AC output. I need X voltage for my amp, so ...
2. What power transformer do I choose, if I want X voltage, of the varied array of transformers available for my design.

I'm sure there are many more variables and options to consider, but that's the starting ones I can see.

~Phil

[martin manning]

I think the question I’m actually trying to present is under what circumstance would you not want to use an artificial center tap as part of the rectifier?

You never want to use an artificial center tap in a rectifier circuit. A Full wave requires a center tap, a Full Wave Bridge gets its ground reference from the bridge. See http://www.hammondmfg.com/pdf/5c007.pdf

[lightfoot]

I think the question I’m actually trying to present is under what circumstance would you not want to use an artificial center tap as part of the rectifier?

You never want to use an artificial center tap in a rectifier circuit. A Full wave requires a center tap, a Full Wave Bridge gets its ground reference from the bridge. See http://www.hammondmfg.com/pdf/5c007.pdf

This I already understand but this point may still be helpful for others.

[lightfoot]

Here’s an image of the Blues Deluxe rectifier because this is the transformer that I’m using although unlike the image it’s currently in a full wave bridge configuration

[sluckey]

I think the question I’m actually trying to present is under what circumstance would you not want to use an artificial center tap as part of the rectifier?

You never want to use an artificial center tap in a rectifier circuit. A Full wave requires a center tap, a Full Wave Bridge gets its ground reference from the bridge. See http://www.hammondmfg.com/pdf/5c007.pdf

This I already understand but this point may still be helpful for others.

If you already understand, why are you asking about artificial center tap in any rectifier?

[lightfoot]

You never want to use an artificial center tap in a rectifier circuit. A Full wave requires a center tap, a Full Wave Bridge gets its ground reference from the bridge. See http://www.hammondmfg.com/pdf/5c007.pdf

This I already understand but this point may still be helpful for others.

If you already understand, why are you asking about artificial center tap in any rectifier?

Because I’m trying to understand why one design would be favored over the other given the same power transformer. It could very well be designers choice and more of a coin toss with no advantage or disadvantage one way or the other though.

[martin manning]

Are you asking what the pros and cons are for FW vs FWB? An artificial center tap (a resistor from each end of the coil to ground, as is done for heater windings sometimes) has no place in a rectifier circuit.

[lightfoot]

Are you asking what the pros and cons are for FW vs FWB? An artificial center tap (a resistor from each end of the coil to ground, as is done for heater windings sometimes) has no place in a rectifier circuit.

No not exactly. I’m referring to the high voltage supply of the power transformer. I believe @pompeiisneaks May have offered as good of an explanation as possible in that each configuration offers a slightly different rectified voltage. Take a look at the rectifier diagram for the blues deluxe that I posted. I’m trying to figure out if I should go back to that rectifier configuration or if I should leave it as a full wave bridge rectifier.

By the way the amplifier in question is an original circuit design I just used the power transformer from the blues deluxe.

[pdf64]

Here’s an image of the Blues Deluxe rectifier because this is the transformer that I’m using although unlike the image it’s currently in a full wave bridge configuration

The image shows a full wave bridge rectifier

The transformer’s HT winding has no centre tap, so a non-bridge full wave rectifier is not feasible.

[lightfoot]

Here’s an image of the Blues Deluxe rectifier because this is the transformer that I’m using although unlike the image it’s currently in a full wave bridge configuration

The image shows a full wave bridge rectifier

The transformer’s HT winding has no centre tap, so a non-bridge full wave rectifier is not feasible.

Part of what may be complicating this discussion is my choice of nomenclature. When I say artificial center tap what I really mean is the ground reference of the bridge portion of the rectifier. It sounds like you’re suggesting that the stock rectifier circuit as shown in the diagram should probably be the one I use?

Additionally based upon image search is that I’ve done of rectifier configurations the one in the schematic was referred to as a full wave rectifier rather than a full wave bridge.

[sluckey]

Here’s an image of the Blues Deluxe rectifier because this is the transformer that I’m using although unlike the image it’s currently in a full wave bridge configuration

That image is a full wave bridge. May not be drawn the way you would like to see it but it is a FWB.

Because I’m trying to understand why one design would be favored over the other given the same power transformer. It could very well be designers choice and more of a coin toss with no advantage or disadvantage one way or the other though.

Designers choice. FWB cannot be used with any economically available tube rectifier. FWB requires only half as much AC voltage (less copper) to produce the same voltage as a center tapped conventional full wave rectifier circuit. The FWB circuit uses the entire secondary voltage all the time, whereas the conventional rectifier with CT only uses half the secondary winding at any given time. Some may consider these characteristics as an advantage.

Regardless of which type rectifier is used, you will never see an artificial center tap used with a FWB rectifier circuit.