Connecting a transformer backward

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Connecting a transformer backward can result in supplying a doorbell with a significantly higher voltage than required. The voltage ratio of 120V to 12V indicates that if the transformer is reversed, it could theoretically supply 1200V. However, this excessive voltage would likely cause a fuse to blow, preventing damage to the doorbell. Therefore, while the calculation of 1200V is correct, the safety mechanisms in place would protect the device from such a scenario. Proper transformer connection is crucial to ensure safe operation.
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An electric doorbell requires a 12 V, 60 Hz ac supply. If the transformer is connected the wrong way around the circuit, what voltage is supplied to the doorbell?

If figured the voltage ratio would now be 120/12, or 10, and 10 x 120 = 1200V. Is this right?

My other idea was that connecting the transformer the wrong way would simply supply the doorbell with 120 V.

Which is right?

Thanks
 
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fromthepast said:
An electric doorbell requires a 12 V, 60 Hz ac supply. If the transformer is connected the wrong way around the circuit, what voltage is supplied to the doorbell?

If figured the voltage ratio would now be 120/12, or 10, and 10 x 120 = 1200V. Is this right?

It is right. And certainly a fuse will blow off to stop this voltage supply.

ehild
 

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