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Honda Service Tester capacitor/condenser tester voltage?

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AshimotoK0:
Just building a bit of kit to test out Honda condensers. (using a scrap 12v ->400v DC generator ) . I have a decent Fluke meter to test the capacitance accurately  but the Service Tester applied a high voltage of several hundred volts in order to check for dielectric insulation breakdown at high voltage. Does anyone know the voltage that the Service Tester generated/applied to the condenser under test? I suspect about 400v DC but I don't want to trash perfectly good condensers by overdoing it.

I think Oddjob used to give his apprentices electric shocks using that bit of kit, so maybe he's my man. Or if anyone has a copy of the service tester manual it may tell you in that. I suspect a lot of Honda capacitors are binned when there is nowt wrong with them ..only to be replaced by pattern parts such as  Daiichi and the like, which are sh*te.

UPDATE : Found these manual scans. Looks like the 70's tester used an electro-mechanical  vibrator to generate the high voltage ( like car valve radios used in the 1950's) ... I am using a solid-state inverter.

 However, I suspect that the tester applied voltage at a frequency of 60hz....  reading the JIS spec. for condenser testing.

Also found the instructions for use in the CB450K0 Black Bomber shop manual. If anyone wants to gen. themselves up on vintage Honda electrics then read the section on electrics in the BB manual  ;D  Link below:-

https://www.dropbox.com/s/typ5a2r2mjaxtvs/CB450%20K0%20BLACK%20BOMBER%20SHOP%20MANUAL%20.pdf?dl=0

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AshimotoK0:
Got the (very serious) boys on the 'Amateur Radio'  forum analysing the schematic.

Think I am going to build a high voltage generator (12v _>400v inverter and switch that at a frequency akin to the max engine speed using a high voltage ignition transistor, whilst heating the metal can of the condenser to a typical 'in service' temperature... as per the 1966 J.I.S. standard .... described in the 1966 Honda Shop manual for the 'Black Bomber' CB450K0. It will be interesting to see how a brand new Daiichi condenser fairs when subjected to this test. As Thin Lizzie would sing .. they have a Bad Reputation  ;D

AshimotoK0:
Wow .... just checked and the price each for a genuine condenser for a CB400F is just over £50

Bryanj:
Ash you can still get the comlete points plate with everything on from your local dealer for just over £100

AshimotoK0:
Got an absolutely fantastic response from the VintageRadio forum on this topic.

Not so much on here though, which is a bit disappointing.
 
Not particularly having a rant but it seems we get pages and pages of posts on here on  the differences between Honda  candy gold paint finishes, so I am beginning to wonder why I bother posting this tech stuff as there seems to be very little discussion.

Anyway, moving on,  I bought a high voltage  insulation tester to 'weed' out condensers , before I build a pukka JIS spec.  tester.

Interestingly, I took a dual capacitor from a Honda twin and a NOS similar one.
Testing the capacitor at elevated temperature, akin to what you get in service, the capacitance was bang on the correct value given by Honda on both the old and the NOS parts.

Also testing the the insulation firstly at 250v, then 500v, then 1000v,  on a single 'static'  test, the insulation was fine on both the used one (Genuine part .. taken from a 1973 bike) and on the NOS one. I also tested a NOS electronic component 'wire ended' one of similar capacitance and voltage spec.

However, there is a 'continuous' test mode on the new tester I bought and when tested on this function (it repeatedly applies the voltage), the used one started displaying a value of a couple of megOhms leakage, whereas the NOS part and the 'reference' capacitor didn't.

So I guess the used condenser is leaky, dynamically and explains why the owner of the bike was reporting excessive arcing at the points, even though on a static test the capacitor tested out fine.

My next 'experiment' is to dig out a brand new Daiichi pattern one and put it through it's paces. This brand has a very bad press but is the pattern part sold by lot's of reputable parts suppliers including David Silvers.

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