DC Pump Aggravation - No Re-Start after Short Power Loss

Sleepydoc · Jul 27, 2018

I can’t recall with the Varios, but the COR 20 enters an error state that requires user intervention to correct.

ksed · Jul 27, 2018

Oh Wow! That’s no good!

wangspeed · Jul 28, 2018

I don’t see any mention of the brand. My Varios 8 always starts back up. I’ve had Jebaos too and they fire right up. I’ve even short cycled them before and they overcome the backflow. Something isn’t right.

I will say I was confused by my Varios 8 at first. There’s a 1 minute delay where it will flash lights before it fires back up after power loss. I checked in on this and it’s done on purpose.

mcarroll · Jul 28, 2018

ca1ore said:
FWIW, I noted the 'back-spinning' problem on my PanWorld AC pump, so it's not limited to DC. I'd imagine any magnetically driven pump impeller would be suceptible. Perhaps direct driven pumps like Reeflo would be less affected.

Other pumps have been designed to prevent this....maybe fair to say "better pumps".

Check out “AC and DC Pumps” – Internet Reefer’s Decoder Ring

ksed · Jul 28, 2018

Interesting, there seems inconsistencies as there are a few that don’t have start up issues and few that do.

Wangspeed appears to have a built in timer in his controller as the light blinks for about a minute. Anyone else that has a Varios and does the same?

madweazl · Jul 28, 2018

redfishbluefish said:
That's a good question. I took it as any and all DC pumps that have a chance of back spin are subjected to this "stalling." Maybe @ca1ore could verify this....he's the smart one who identified the issue with my Waveline DC6000.

Which generation Waveline? Our 75g has a DC6000 (first gen) and this hasn't happened (39" head height). This event would be triggered every weekend because of the way I do water changes.

redfishbluefish · Jul 28, 2018

madweazl said:
Which generation Waveline? Our 75g has a DC6000 (first gen) and this hasn't happened (39" head height). This event would be triggered every weekend because of the way I do water changes.

How would I determine the "generation?" It's maybe 4 - 5 years old....as a guess. If it helps, here's a pic of the controller:

I am curious how you do water changes where the pump is off and then back on within seconds. This "stall" phenomenon only occurs when we have a power outage, and within seconds the power comes back on. Try unplugging your pump and wait 3 - 5 seconds and plug it back in and see what happens.

madweazl · Jul 28, 2018

Is it the Apex ready model?

redfishbluefish · Jul 28, 2018

madweazl said:
Is it the Apex ready model?

Nope!

shred5 · Jul 28, 2018

https://www.coralvue.com/reef-octopus-auto-time-delay

This is made for a skimmer but it would work for a pump..

I have not had issues with dc pumps restarting. I have had ac pumps not restart.

Mark Gray · Jul 28, 2018

Interesting I have my larger system on a UPS but not sure how long the pumps will run on it, I did this more to protect the Apex system from lighting and power surges and brown outs.

redfishbluefish · Jul 28, 2018

shred5 said:
https://www.coralvue.com/reef-octopus-auto-time-delay

This is made for a skimmer but it would work for a pump..

I have not had issues with dc pumps restarting. I have had ac pumps not restart.

I have purchased a "delay re-start" outlet that will delay the pump coming back on for three minutes.....for only 9 bucks......see post #22. When it arrives I'll test it out and let you know if it works.

madweazl · Jul 28, 2018

redfishbluefish said:
Nope!

You have a first gen Waveline, then. When was the last time it was torn down and cleaned?

redfishbluefish · Jul 28, 2018

madweazl said:
You have a first gen Waveline, then. When was the last time it was torn down and cleaned?

It's on a six month cleaning schedule. That's the other difference I noticed over the MAG pump I originally ran. This DC guy gets some pump snot on the impeller, and it stops working...about 8 - 10 months of use.

ca1ore · Jul 28, 2018

mcarroll said:
Other pumps have been designed to prevent this....maybe fair to say "better pumps".

Check out “AC and DC Pumps” – Internet Reefer’s Decoder Ring

Well, 'better' is of course highly subjective. I've been looking for a long time for a 'better' alternative to what I currently use. So far alternatives create more problems than they solve. As a point if clarification, AC pumps that prevent reverse operation is not the same as the issue under discussion here. Back spinning is where the impeller is pushed backwards by drain down but the motor is attempting to run in the correct direction. I'm unaware of any pumps with features to prevent this. Largely moot though, as programming a short startup delay into apex, or any other device solves the problem just fine.

madweazl · Jul 28, 2018

redfishbluefish said:
It's on a six month cleaning schedule. That's the other difference I noticed over the MAG pump I originally ran. This DC guy gets some pump snot on the impeller, and it stops working...about 8 - 10 months of use.

Yea, they get pretty nasty in there.

mcarroll · Jul 28, 2018

ca1ore said:
Back spinning is where the impeller is pushed backwards by drain down but the motor is attempting to run in the correct direction. I'm unaware of any pumps with features to prevent this

I'm not familiar with the phenomena so I'm at the mercy of descriptions here.

If it has nothing to do with the anti-reverse technology, are you suggesting that the pump just doesn't have the immediate torque available to defeat the backward rotation caused by the backward-flowing water?

If so I think that (startup torque) is related to the static magnet size in our DC and AC pumps, right?

I don't think I've ever had this happen, but I'm also still trying to make sure I understand correctly what you're describing.

jda · Jul 28, 2018

This is all conjecture, but I think that a lot of it has to do with soft-start also. Most "DC" pumps start soft and do not have a lot of wattage available in the beginning. If the controller senses a voltage interrupt, then they shut down (similar to how a Tunze will beep at you). Real AC pumps have all of the available torque from the instant that they turn on, plus a lot of them can run in either direction.

shred5 · Jul 28, 2018

What dc pump is it?. I have a RO DC pump and when I moved in the power was on and off all the time when it was windy or raining. Some times just a flicker but mostly several seconds and sometimes longer and never had a issue. I also used RLSS DC pump and never had this issue but never at my new place with the power issues.

redfishbluefish · Jul 28, 2018

mcarroll said:
I'm not familiar with the phenomena so I'm at the mercy of descriptions here.

If it has nothing to do with the anti-reverse technology, are you suggesting that the pump just doesn't have the immediate torque available to defeat the backward rotation caused by the backward-flowing water?

If so I think that (startup torque) is related to the static magnet size in our DC and AC pumps, right?

I don't think I've ever had this happen, but I'm also still trying to make sure I understand correctly what you're describing.

Matt, I think you might be onto something here. This is what I'll call smoke up the old wazzoo theory...because I have no idea what I'm talking about, so take what I have to say with an enormous grain of salt. DC pumps actually run AC....they convert that small DC voltage to AC for the motor to start to spin. I speculate that one of the reasons for slow start up is that the voltage is very low (low torque). If the pump is running in reverse and the pump now receives voltage to restart....and a slow start is needed to get the rotor spinning, it's not going to happen. Again, I want to stress that this is an idiots speculation as to what is going on....and I'm the idiot. If the motor doesn't slow start, it won't start at all. Need to stress again, this is speculation on my little brain's part....could be simply blowing smoke!