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# Need help w/full wave bridge rectifier

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I am seeking advice on how to determine what voltage and current ratings a bridge rectifier is required for a charging circuit. The circuit consists of a stator, 12 volt lead acid battery, 12 volt DC accessories, and the rectifier. The charging circuit produces a maximum of 7 amps DC current.  The stator's output is between 180-200 volts AC. This circuit does not rely on a voltage regulator to prevent the possibility of voltages higher then 16 volts DC being sent to the battery and components that maybe damaged above 16 volts DC. I know the current rating for the bridge rectifier is 20 amps. However, I do not know how to determine if the rectifier's voltage rating is determined by the 13.0 to 15.5 volts DC requirements of the battery and accessories. Or closer to the tolerance neccessary to handle the input voltages upwards to 200 volts AC or higher.
I attempted to use a 25 amp. 50 volt bridge rectifier. However, DC voltage going to the battery is between 15.7 - 16.1 VDC.  Which is very close to the max. tolerance of certain components. The next size I have readily available is 400 volt 6 amp bridge rectifier.
Any help will  be most appreciated.

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I don't think it would be a wise thing to take a 180-200VAC signal, rectify it and try to charge a battery without a regulator!!! The batteries internal resistance is probably what's holding the voltage down.

As for the diode voltage rating.... you are interested in something called PVI (peak inverse voltage). It is the max voltage that can be applied in a reversed bias condition before the junction will break down.

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Hi Matthew,

Is this about an Outboard Motor?

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Hi Ante,

I failed to recall that I had posted a similar post seeking help with understanding rectifiers on this particular forum. My apologies to those who shared their time and knowlegde in response to my original post. I assure you your efforts in helping me are very much appreciated and have not gone to waste.

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