Hello, I starterd to see something that I hope doesn't become a trend and thought I would bounce it off everyone here to see if they are having simular problems. On our 2008k machines s/n starting with 5KOS I am seeing failures on the blood pump motor. More specifically what I am seeing is that the motors are starting to stall or fail to restart, especially at lower pump speeds. I usually am seeing A.11 or A.24 error codes on the blood pump. These machines have around 8-10 thousand hours on them.
Is anyone else seeing a simular trend or is this the normal life of the 2008K blood pump motors?
I look forward to your responses.

Yes, we are seeing the same thing here, I had 2 different kmach's in 2 different facilities just last week. The 1st one had 14000 on it and it gave me an A.11, Tech support told me it was 1 of 2 things the rotor sensor or the LP955 BOARD. Well needless to say it was the motor/tach assy. The 2nd one was 4 days later and had the same A.11 Alarm and I did not even bother with tech support I swapped the motor/tach assy with a known working and the A.11 followed the motor/tach assy. I do believe that we may be seeing a trend here. Anyone else with the same problem?

change the brushes it can be done. im going to show how is done on a video.

A.11 and A.24 problems are a problem in our unit as well. Replacing the blood pump motor assemblies resolves both problems. Usually replacing LP955 or LP956 only works for E.XX problems.

We have been having some difficulties also. S/N 5KOS at 2 clinics with about 8-10,000 hours and I had 3 at this clinic last week all A.24. They will begin to stop during treatment, these are 6KOS machines with 4-5K hours. It seems odd that the pump motor tach assembly is the only part in the BP module that Fresenius will not exchange. However just swapping the affected parts is cheaper than a whole module exchange.

Ummm..folks...

8,000-10,000 hours on machines and you're NOW seeing problems with blood pumps? Wouldn't this be considered somewhat normal? Isn't there a life expectancy on ANY pump in a dialysis machine of approximately this same amount of time? These parts don't last forever, people.

Count your blessings!

Let me throw this out there, If your blood pumps are showing problems with alarming errors/wear, look at how your clinical staff is loading the tubing into your pumps, if there is any manual manipulation of the tubing, the "K" blood pump will have all sorts of problems. The staff "must" load the tubing using the control buttons on the pump and not turning by hand, the sensor on these pumps will not tolerate physical turning by hand....

You're not alone, I have lost 8 in the last 6 months. 5-6K hours

You are oh so right!! Any motor/pump will not last forever. These blood pumps cannot be turned backward it screws up the tach. Replace brushes? Be more specific give us details, we want details.... Does the big F approve of this?

I've been seen the same problems with the blood pump motors on machine with 5 to 6,000hrs. Once I fiqured out how to take the motor apart with out breaking anything I've found in most of them the brushes were fine. After cleaning out the brush dust and soldering the power wires instead of the spade crimps that fresenius uses and there back to running with out any problems. I think the loose power wires are the main problem along with the build-up of the brush dust. I have several that have been going now for greater than 1,000hrs so far.

Hey old F guy, I was on the understanding that these pump motors were not servicable because they can't be taken apart without damaging the motor/tach assembly. Are you saying you have figured out a way to get around this?

dhohunter is exactly right. The tach assembly if pretty flimsy side and will not tolerate the pump moving in the opposite direction. I have found that is where the problem lies. The staff are used to the H machines and yank the lines out of the system like they used to. Doesn't work with this tach setup.

You can get access to the brushes by going through from the gear box end. That does not require removing the tach from the shaft which is on the opposite end of the motor. We have been sending motors to H&S for rebuilding and they have been replacing the brushes and the inner bearing for about 70 bucks less than the price of a new motor. About ten percent of the motors that H&S rebuilt are failing again fairly soon (within a few hundred hours) after we install them. That does not seem like a very good success rate to me. They are locking up and/or becoming very noisey. To my knowledge Fresenius does not recommend any rebuilding of these motors, nor do they sell rebuilds themselves.

quote:

Originally posted by Midwest-Biomed:
Hey old F guy, I was on the understanding that these pump motors were not servicable because they can't be taken apart without damaging the motor/tach assembly. Are you saying you have figured out a way to get around this?

Yes, just as "guess name" said you take apart gear box and remove and take apart motor with out ever touching the the bellhousing / tach assy end of the motor. You will need a pair of c-clamp plyers to remove a clip from the motor shaft. I only trashed a couple of motors before I got it down pat. In most cases just soldering wires and cleaning have got them back going again for me.