Double tapped capacitor cross-connection

Specific Inspection Topics Electrical Inspections
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I came across this on my inspection today. There were MANY electrical defects on this inspection but this one has me scratching my head and wondering, how bad of a defect this…just for my curiosity. Its definitely a double tap but what might the purpose be? I’ll be referring out to an electrician but do any sparkies or inspectors want to chime in on this one?

It appears to be a capacitor double tapped between a 15 amp circuit and 20 amp circuit. Some DIY line conditioner or something? Is that 480 VAC or 48 VAC stamped on the capacitor?? :man_shrugging:

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Thanks Christopher!, and @gwells! This makes sense :+1: I’ll admit I didn’t perform a quick search on the archives.

Edit:
With that info though, there are still 2 wires under a breaker terminal that appear to only be rated for one wire? Wouldn’t that still be problematic? I believe it is.

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Unlikely to be a band-pass filter. It’s more likely to be noise or arc suppression.

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If the circuit breaker is only listed for a single conductor then yes it’s an issue. I hate when people call receptacles plugs. The voltage listed is 480.

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I would have thought the use of a post-it note might be more annoying since those tend to fall off anyway and solve that pesky labeling problem :wink:

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How is a capacitor going to suppress an arc?

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I am out of my league here, George and basically guessing but, couldn’t a properly rated capacitor act as a temporary energy storage device? The mother board for my PC has 20 capacitors. They help stabilize the power supply by filtering out voltage fluctuations and noise.

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Yes, in a DC circuit. No, in an AC circuit.

The capacitor will not suppress an arc or filter any appreciable amount of noise.

The most it would do is bring the current closer to being in phase with the Voltage by an almost immeasurably small amount. A capacitor of that size is completely useless for PF correction.

Old home automation systems and some other communication systems use the electrical wiring to carry their signal. A capacitor serves as a bridge for the signal.

As you know, the two legs are electrically and mechanically continuous. However, there is a coil between them (the transformer’s secondary). Anything riding on the electrical wiring that has a high frequency will not pass through the coil.

Conversely, a high frequency signal will pass through a capacitor. The most convenient place to put the capacitor is in the electrical panel.

There is no other practical use for a capacitor of that size in an electrical panel other than as a band-pass filter being used as a communication bridge.

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As always, George. Thank you for the explanation.

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Don’t worry I didn’t either. Google found it for me… :sweat_smile:

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