saba: Bodensee-Automatic 3-D motor capacitors.

Respected Members. 
I am restoring a very nice Saba Bodensee aut.3/D and I need to replace the two motor capacitors.  The technical indication is 0.5 uf/300volt and 0.33 uf/630 volt alternating current capacitors, very very difficult to find in the market. 
I performed the replacement with two direct current capacitors and the motor tuning unit is working satisfactorily. 
Replacing alternating current capacitors by direct current capacitor has some potential risk? 

thanks in advance, Bruno.

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There should not be a risk if the rated DC voltage is at least 1.4x AC voltage (to cope with the maximum  of the sinusoidal voltage.
Of course no electrolytics....

I always used 500 V and 1000 V types respectively (for a dozen SABA Automatics). That happened years ago and I never had a complaint.

You may have to combine to arrive at the correct value for resonance.

At the small power being involved the power factor (delta phi) is not important.
MP or MKS or FKP etc. types should be suitable for.
 
Only at higher power applications special AC rated capacitors would be advisable.

Good luck!

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Hello Herr Birkner,
Thank you so much by your clearly and supported explanation.  With your suggestions my Bodensee motor tuning is working perfectly. 
Greetings, Bruno.

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