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Adding a capacitor to a DC motor

I ordered an inline blower motor that runs off of 12V 6A found here: https://www.amazon.com/gp/product/B0166S2PA2/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

So I decided to buy a 12V 8 Amp AC to DC adapter for the motor, 8 Amps to give it room for Its startup current, found here: https://www.ebay.com/itm/Quality-12V-DC-8A-8-amp-96W-POWER-Supply-ADAPTER-Transformer-for-LED-Strip-CCTV/164220904080?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649

When I originally hooked this inline blower motor up straight to a 12V car battery, I tested it with an “amp clamp” and It pulled 0.3 Amps, even on start up, But when I hooked it up to the 12V 8 Amp AC to DC adapter for inside use it turns on for a split second and then turns off continuously like there’s an over current regulator in the adapter.

Would a capacitor work for this inline blower motor and how would I size it without getting to much overcurrent to the motors windings or blowing out a capacitor from it being the wrong sized capacitor?

A 10 Amp fuse was required by the inline blower motor manufacuter and installed.


It appears that we do not make any of the products you are using, so I do not have any specific suggestions about what is going on or what might fix it.

However, keep in mind that motors usually draw many times their free running current when starting, and that might be too quick for your meter to measure. So, you might consider looking at your setup with an oscilloscope to try to isolate the problem and understand what is going on better.

- Patrick