Osmolator Issues

[jkohout]

I'm trying to figure out the problem with my osmolator. I recently purchased a used one and it doesn't seem to be working properly. I'm not sure if it's the pump or the controller.
Initially when I received the controller, the pump wouldn't move. When the controller/pump were unplugged the impeller would move freely but when it was turned on it would lock up. After several times connecting and disconnecting the pump if finally started to spin - but varying speeds. Another thing that is unusual is that when the 'pump on' light is lit the 'level' light also lights up - both lights are almost flashing as they vary in intensity.
All of the testing was done in a bucket of water. The sensors seem to be working fine. Using a 12v power supply since original 11v was not supplied. There didn't seem to be any corrosion on pcb itself. There was a little on the power connection.

Any suggestions on what the problem might be?

thanks,
jeff

 

[rvitko]

First check that your power supply can supply enough power, it sounds like the unit is starved for power, it should put out between 9 and 12V DC and the critical part is that it can deliver at least 1200mA if it is 12V and 800mA if it is 9V. The tip should be 2.5 by 5.5 mm tip positive. It is possible the pump is bad or the wiring/terminals are corroded and causing excessive power draw as well.

 

[jkohout]

Ok. I think I have a bad pump and controller. I hooked up the pump to a new osmolator. It runs for about 2 minutes and then slowly shuts down.
Now, I hook a new pump up to the old osmolator and it will run fine for about a minute until the pump will slowly turn off. So it looks like I am dealing with 2 issues - old/bad pump and a controller issue?

thanks,
jeff

 

[rvitko]

Depends on the age of the controllers, Up until 2008 the controllers had an 800mA limiter and they now have a 1200mA limiter, what you describe is definitely the current limiting switch opening as it heats up from the over draw, this could be the pump, but it could be the current limiter which was upgraded when we switched to a redesigned pump with a double oring seal. This new pump will only work at 9V with osmolators with the 800mA limit. It is also possible for corroded wiring or connectors to the pump to raise the current draw past the preset limit. On an old osmolator we can add a second limiting switch but you have to upgrade to the new transformer as the old transformer could only provide 800mA and the new one can provide 1600mA. This limiter is a safety that prevents the basic logic functions from being starved of power and unable to perform the safety functions.