12V 0.25A E12 Christmas Lights Fuse Bulb For 20 Light Vintage Sets Pifco, 796C

12V, 0.25A E12 fuse bulb for 20 light vintage Christmas light sets. This lamp is rated at 12V, 0.25A.

The bulbs used in vintage sets tend to be permanent contact types. This means that when there is a failure the bulb fails to a short circuit. This is useful as it prevents the whole set from going out when a bulb fails. The draw back is that the 12V dropped across the failed bulb is now shared between the other 19 bulbs in the set. There is a consequential increase in the current flow from the nominal 0.25A, 250mA. This can quickly lead to a chain reaction causing more and more bulbs to fail so some additional protection is required by way of this fuse bulb. When the current exceeds 0.25A then the fuse bulb will fail to an open circuit and the whole set will go off. The reality is that the fuse bulb will not fail very quickly, or never at all,  when only 1 bulb has failed but it will go open circuit if 2, 3 or more bulbs fail. This will prevent you from having to replace multiple bulbs in your set and keeps things safe.

It is important to keep your eyes peeled for failed lamps and get them replaced as soon as possible.

Lets look at the lamp specification:

• Lamp Voltage 12V AC or DC

• Lamp Current: Typically 0.25A, 250mA
• Colour: White

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