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3 phase rectifier


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Is it normal for a pipe organ action to be driven off a 3 phase supply? I'd have been surprised to find a church which had 3 phases even coming in to the building. Is it to give better smoothing than is possible with 1 phase?

 

Quite a few have 3 phase blowers and lighting.

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Quite a few have 3 phase blowers and lighting.

 

Hi

 

Most large - and some no so large - organs are driven by a 3-phase supply, and running all 3 phases into large buildings to (theoretically) equalise the load on the phases was pretty common. Smaller organ blowers will run quite happily on single phase.

 

I know of one church where 3-phase mains was supplied solely for the organ blower - everything else was on just one phase. That led us a song & dance trying to find why the blower wouldn't run - until I found a blown fuse in one leg of the 3 phase supply!

 

Every Blessing

 

Tony

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Thanks for that info - my only experience of 3 phase electrics has been in theatres, with (eg) 100kW on each phase, separation between (eg) FOH, Stage and Grid and lots of attention to keeping lanterns fed from the different phases more than 2m apart, so I've always associated it with very large power requirements and the need for physical separation.

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Is it normal for a pipe organ action to be driven off a 3 phase supply? I'd have been surprised to find a church which had 3 phases even coming in to the building. Is it to give better smoothing than is possible with 1 phase?

 

 

The main line railway 3rd rail 750Vdc supply (south of London) is apparently derived from 3-phase using 6 diodes...

 

Even without smoothing, the rectifier output never falls to zero; you get 6 peaks every cycle instead of 2.

As demonstrated here, near the bottom of the page

 

Some 3-phase blower motors are very old, very compact for the power rating, and very efficient!

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The main line railway 3rd rail 750Vdc supply (south of London) is apparently derived from 3-phase using 6 diodes...

 

Even without smoothing, the rectifier output never falls to zero; you get 6 peaks every cycle instead of 2.

As demonstrated here, near the bottom of the page

 

Some 3-phase blower motors are very old, very compact for the power rating, and very efficient!

 

An excellent answer to the question. Thanks for posting that link.

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Maybe just for interest.

 

I first came to Bournemouth in 1960.

 

Two years before three of the churches here had their blowers changed to AC. (In one case

the old blower was abandoned under a vestry floor). The DC supply had come from

Bournemouth Corporation Trolley Bus supply. These ran past each of the churches. A few

shop lifts were also supplied. All the working Trolley Buses were, within a few years, sold to

Blackpool. The massive blower for the Pavilion Compton is 3 phase 200v AC. When the

voltage was altered to the 240v norm. A transformer (still in use) was supplied.

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  • 7 years later...

On the subject of three phase rectifiers, can anyone supply me with a data sheet or instructions on how to change the DC output voltage on the unit attached in the photo, or manufacturer and model number if you have it.

Thanks,

Jonathan

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