eem2am
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Hello,
How many overvoltage transients occur in the domestic mains electricity supply of UK and/or USA ?
(how many per year?)
-Basically, I am referring to overvoltage spikes where the Mains voltage goes up by 20% or more.
Page 2 of the following has a diagram stating that the mains has 800V transients for 200us per day……….is it really that often at this high voltage?
**broken link removed**
it also says that for 60us per day, our mains is 1200V !...can this be so?
- - - - - - - - - -
Background………….
Since LEDs last for 10 years, we are making domestic mains LED lights.
Since the product must last for 10 years, it must be robust.
Therefore, we want to ensure that the product is not damaged by mains overvoltage transients.
To mitigate such transients, we could place MOVs just after the input EMC filter.
However, it is known that MOVs do not provide transient protection for long.
-Once a MOV has “broken over” a few times it is seriously compromised and on the verge of failure_open_circuit.
-Once failed open, the MOV offers no further protection against transient overvoltages.
In a few cases, the MOV can fail short and the lamp is then useless …..always blowing the fuse when ON.
How many overvoltage transients occur in the domestic mains electricity supply of UK and/or USA ?
(how many per year?)
-Basically, I am referring to overvoltage spikes where the Mains voltage goes up by 20% or more.
Page 2 of the following has a diagram stating that the mains has 800V transients for 200us per day……….is it really that often at this high voltage?
**broken link removed**
it also says that for 60us per day, our mains is 1200V !...can this be so?
- - - - - - - - - -
Background………….
Since LEDs last for 10 years, we are making domestic mains LED lights.
Since the product must last for 10 years, it must be robust.
Therefore, we want to ensure that the product is not damaged by mains overvoltage transients.
To mitigate such transients, we could place MOVs just after the input EMC filter.
However, it is known that MOVs do not provide transient protection for long.
-Once a MOV has “broken over” a few times it is seriously compromised and on the verge of failure_open_circuit.
-Once failed open, the MOV offers no further protection against transient overvoltages.
In a few cases, the MOV can fail short and the lamp is then useless …..always blowing the fuse when ON.
