strange problem: varios 6 pump makes a few spins then stops

[astroboy]

I've had it for seven months worked fine until this evening. The impeller and interior of the pump are clean, impeller turns nicely, this still happened after a soak in bleach and then CLR. Same thing happens when the float switch is turned off, or when it's turned on and the float is in the "keep pumping" position. 

 

I hooked it up to a different Octo controller and the same thing happens. This second controller came with a VarioS-2S skimmer pump. Does anyone know if the different VarioS pumps use the same controller? They look the same but on the back they have a number: C 066404 for the VarioS 6, and C069200 for the VarioS-2S. Not sure if this is a model number or just some sort of serial number....

 

I also switched out all the cables from the two controllers/pumps. No difference, a few turnovers and that's it. 

 

One thing. It turns over (and then stops) when I plug the power cable into the controller. If I turn on the on/off button nothing happens regardless of the cables & controllers I'm using. I do see a spark when I plug the power cable into the controller and offhand I would think that was a problem but the pump still fails with the second controller, with no spark. Perhaps the jack on the first isn't working so well.

 

All this seems to indicate the pump itself is at fault but  I can't think of what kind of hardware (solenoid & rotor?) would turn over a few times and then stop, when everything is clean. Sometimes it turns over a few times more than others but for never more than a second or two. 

 

Any ideas of what the problem could be?  I'm really puzzled here.

[DaJMasta]

My guess: fault protection.  Briefly turning on only to turn off says that there's some mechanism in there to prevent damage when running it when there's a problem that's kicking in and stopping it prematurely.  Whether this is a real fault being caught or the fault detection mechanism being faulty is harder to gauge, and exactly what kind of protection is triggering (probably not heat since it's so quick, but maybe rotation detection or current detection from the driver)... much harder to say.

 

If there is any kind of error code/status LED/app message, that's probably the best way to determine it, but that sort of falls to how transparent about their hardware they want to be with the consumer as to whether it's even shown.

[astroboy]

Well, I soaked the whole thing in CLR for 16 hours after which it worked just fine. I'm sort of surprised since it looked clean before the first soak (1 hour) and even cleaner, if that was possible afterwards. Very strange. There must have been some buildup of something that was hard to see with the naked eye.