View Single Post
  #6   Report Post  
Posted to uk.d-i-y
NT[_2_] NT[_2_] is offline
external usenet poster
 
Posts: 3,565
Default Motor start capacitor - value ?

On Sep 10, 9:53*pm, cynic wrote:
On 10 Sep, 11:45, robert wrote:

Have acquired an old pedestal drill with a
British Houston Thompson single phase 1/4hp motor
marked KF TD3205 type BS 2408


The motor start capacitor needs replacing but it has no visible markings
on it *due to several paint coatings !


With capacitor removed the motor will run with a hand start and I can
hear what I assume is a centrifugal switch clicking on spin up and spin
down.


Any advice on what size capacitor to buy and try ?


A 70 watt burner motor takes a 4 microfarad. Multiplying up a 1/4 hp
should be about 187 watts so try as a beginning 11 or 12 microfarad.
Make sure any cap you try is rated for mains ac. if it helps you could
use 3 of the burner motor caps in parallel. I got mine from Farnell
Components a few years ago


IIRC motor caps need to be rated to higher than mains voltage, typ
600v.


NT