rule of thumb for run caps?

[The Cobbler]

is there a rule if thumb for run capacitors , example . original is a 35/5 uf . would a 40/5 uf be suitable?
not for me, selling a 40/5 locally & someone is asking if it would work in place of a 35/5.
Thanks

 

[Wrench97]

I would use what the motor calls for, exception being you can use a higher voltage rating.
That said I have seen guys sub in caps rated higher in a pinch with mixed results.

 

[The Cobbler]

^^ thats what I thought & recommended he find the correct one
tks

 

[Jim greengo]

I little oversize usually isnt a problem,just dont use an undersized cap.

 

[u3b3rg33k]

40/35 is 15% oversized. I wouldn't do it. put the right size on it, or you'll put more amps (heat) in the windings where you don't mean to.

 

[American Locomotive]

Capacitor tolerance is typically +/- 5%. 40 uF is a bit much, and the motor will likely draw too much current.

 

[exmaxima1]

35/5 is needed