Proper Grounding Techniques

Eric Smith eric at brouhaha.com
Sun Mar 13 13:18:18 CST 2005


David wrote:
> Considering that resistors might open, but rarely short...i would expect
> this to actually be parallel....

Jim wrote:
> No, the resistor is there to protect the engineer, not the equipment,
> hence series.

If they're in series, but one fails open, it's not going to be protecting
either the engineer or the equipment.

If you have two resistors in parallel, and one fails open, you'll still
have some protection.

If you're really worried about a resistor failing as a short (which I've
only ever seen once), you could use four resistors, with two parallel
pairs in series.  Then any one resistor can fail either open or short,
and you'll still have some protection.

Eric




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