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Reasons this is sometimes done:<ol>

<li>To get higher power dissipation.

<li>To get higher voltage capability.

<li>To get lower parasitic capacitance.

</ol>

For 1 and 2 the "normal" answer is to use a resistor rated for the required power or voltage in the first place.  However, there are some advantages to using multiple smaller resistors.  You don't have to stock another part, you can buy the smaller part in higher volume, and you can control how the heat is spread out.

#3 is because while the resistance of multiple resistors in series increases resistance, the parasitic capacitance decreases.  For example, consider individual resistors that are 2 k&Omega; with 5 pF parasitic capacitance across them.  Putting 5 of those in series yields 10 k&Omega; with 1 pF parasitic capacitance.

We can't tell what the engineers at Tesla had in mind here from just this picture.  We can't even know what parallel/series combination those resistors are in.  Perhaps each string of 5 resistors is one power resistor.  Maybe it was convenient to have these power resistors long and thin.

Higher voltage capability is probably not the answer since the resistances are low.  If those are 0805 packages, then &frac18; W is about the limit.  That would be reached with only 16 V across each 2 k&Omega; resistor.  0805 resistors have considerably more voltage capability than that.  Put another way, you could only put 80 V across a string of five resistors anyway.  Unless this is for absorbing short high voltage transients, this is not the reason.