Suntester Power timing light

I'm new to this forum and I am looking to properly identify and how to test this component. It is from a vintage Suntester power timing light Model 45XA, 6-12vDC.

If anyone can help in describing how it functions and how to correctly test the components I would greatly appreciate it. The component is the brown cylinder, from Industrial COND. Corp. inscription reads: .4-.4-2.5-.028 MFD 600V.D.C

Rgds, Mick

  • \$\begingroup\$ How many wires coming from the brown cylinder? \$\endgroup\$ Jan 4, 2016 at 15:17

2 Answers 2


It looks like what you've got there is a capacitor with multiple connections.
It is rated for 600Volts DC, and has the values of 0.4µF, 0.4µF, 2.5µF, and 0.028µF.

There should be one common lead and four others (five in all.) From the common to each of the leads you should measure one of the given capacitances. I can't tell you how to figure out which lead goes with which value.

Don't expect high accuracy - the measured values may be as much as 50% from the given values. The part itself isn't likely to have been high precision to start with, and will probably have gotten worse as it aged.

You would test the capacitance with a multimeter that has a capacitor function. The given values should be well within the range of a typical meter.

Checking that it can still withstand 600 Volts is a different problem, and I can't give you an answer for that.

You might check the leakage for the various leads - if it is high then it is bad. An easy way to check this is to discharge the capacitor (connect all leads together then disconnect them) then measure the DC-resistance from the common to the other leads. Any low resistance means a shorted capacitor. This will only tell you if the leakage is catastrophic - it might be high resistance, but still have too much leakage for the circuit to work right.


"the component is the brown cylinder, from Industrial COND. Corp. inscription reads ;- .4-.4-2.5-.028 MFD, 600V.D.C" That looks to me like a 0.028 uF (micro Farad) (= 28 nF) capacitor with a 600 VDC rating.

You can test this capacitor for a short by desoldering it from the circuit and measuring it's DC resistance with a multimeter. The meter should read a very high value after a few seconds. This does not guarantee that this capacitor is OK though, for that you need a proper component tester. You can buy simple component testers from China on ebay for $ 20.


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