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d2mini
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Yes.
I have always suspected the flow was low. This just confirms it with an actual number.
DC Controllable Pumps vs AC Pumps
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I have always suspected the flow was low. This just confirms it with an actual number.
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So....
I just got a Jebao DCP 18000 in today and hooked it up.
The watts drawn are NOT dropped at all one bit vs the high head pressure against it OR it's 29.5' head hight rating is laughing at me.
I'll have to look at this again tomorrow but wanted to put this in front of other eyes. @gcarroll I think will be interested in this.
Controller can increase in 1% increments from 30% to 100% and will then report what the watts are being pushed to the pump. To me this is happening: The controller is, well, controlling the output and has no input from the pump on what kind of pressure its getting. This may be a good thing for high head applications but not good for those trying to conserve electricity.
I just got a Jebao DCP 18000 in today and hooked it up.
The watts drawn are NOT dropped at all one bit vs the high head pressure against it OR it's 29.5' head hight rating is laughing at me.
I'll have to look at this again tomorrow but wanted to put this in front of other eyes. @gcarroll I think will be interested in this.
Controller can increase in 1% increments from 30% to 100% and will then report what the watts are being pushed to the pump. To me this is happening: The controller is, well, controlling the output and has no input from the pump on what kind of pressure its getting. This may be a good thing for high head applications but not good for those trying to conserve electricity.
ksed
Valuable Member
These flow numbers are on a skimmer?So....
I just got a Jebao DCP 18000 in today and hooked it up.
The watts drawn are NOT dropped at all one bit vs the high head pressure against it OR it's 29.5' head hight rating is laughing at me.
I'll have to look at this again tomorrow but wanted to put this in front of other eyes. @gcarroll I think will be interested in this.
Controller can increase in 1% increments from 30% to 100% and will then report what the watts are being pushed to the pump. To me this is happening: The controller is, well, controlling the output and has no input from the pump on what kind of pressure its getting. This may be a good thing for high head applications but not good for those trying to conserve electricity.
BTW that pump looks very close to the Waveline.
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You mean the waveline looks very close to a Jebao.
The waveline is a modified Jebao from what I know. Uses a better prop, much better driver, and controller.
Yes, those numbers are from my skimmer using a 1" flow meter going to 3/4" pipe and venturi so the flow meter is not restricting.
https://www.reef2reef.com/threads/mtc-mvx-skimmer-review.252436/page-8
The interesting thing is I was able to see Watts used go up and down when using my waveline dc 12000 reflecting the flow rate changes when swapping out different mazzei injectors like I should but not nearly the drop like an AC pump would have. So it seems the controller of a DC pump is the "weak" link depending on how you look at it but definitely if looking at power efficiency.
With the same mazzei injector and setup as the DCP18000 the waveline was pulling 146watts from the wall outlet, 250gph flow, and pulling about 26scfh of air. Which lines up with the DCP 18000 at 70% and the DCP is rated for less watts (it's also 36v vs 24v of the waveline).
(Edit: and that 70% rating lines up well as the waveline dc12000 has a rated max flow rate at about 67% of the dcp 18000)
What I will do eventually over the next few months is swap out the injectors singly and with my dual venturi modification and see if it also shows very slight varience in watts used.
I can't wait for it to warm up outside and push water straight up 2" pipe and use the 2" flow meter.
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And to add those are all initial snapshot numbers. I'm leaving the pump running at 100% over the nexf few days to get a running average. It will probably change the numbers though most likely very minimal. Like the flow will most likely go up a bit out of all those numbers.
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And FWIW here's previous numbers I had tracked in that MTC skimmer thread including using a 150watt Mag 1800 (big drop in watts pulled). I wish I had the flow monitor at the time.
Brew12
Electrical Gru
A couple of quick thoughts to share.
Ribbed piping such as flexible PVC is bad for flow. You want nice laminar flow along your pipe walls which the ribs prevent.
You would benefit from not reducing the piping size at the immediate outlet of the pump.
A good AC pump will always be more efficient than a good DC pump when run at 100% load.
Pressure and flow are characteristics of the pump impeller, not the motor and/or controller. The motor is only the prime mover and has no impact on how flow drops off with pressure.
As you make more improvements to your return piping in other areas the impact of the 3/4" flow meter will become larger. Piping size flow is all about area. A 1" pipe has an area of 3.14sqin and a 3/4" pipe has an area of 1.77sqin. Your flow seems to be so low now so that this is not an issue but it may become one in the future.
Ribbed piping such as flexible PVC is bad for flow. You want nice laminar flow along your pipe walls which the ribs prevent.
You would benefit from not reducing the piping size at the immediate outlet of the pump.
A good AC pump will always be more efficient than a good DC pump when run at 100% load.
Pressure and flow are characteristics of the pump impeller, not the motor and/or controller. The motor is only the prime mover and has no impact on how flow drops off with pressure.
As you make more improvements to your return piping in other areas the impact of the 3/4" flow meter will become larger. Piping size flow is all about area. A 1" pipe has an area of 3.14sqin and a 3/4" pipe has an area of 1.77sqin. Your flow seems to be so low now so that this is not an issue but it may become one in the future.
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d2mini
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I misspoke early in the thread and I think corrected myself later on... the interior of the flow meter is 25mm (.98").
Its just the imperial to metric couplings that convert down to 3/4". So it's a much shorter chunk than than going through the entire flow meter if it was all 3/4".
That said, i'm in the process of aquiring new fittings (not an easy feat at all) that are G 1-1/4". BSPP threaded stuff is insanely difficult to source.
Now looking at the Vectra that has the 1" coupling on the outlet, I'm down to two pumps as a possible replacement.
The Fluval SV6 (3434 gph) and the Current USA eFlux DC 6011 (3170 gph).
If you look at the flow I'm getting with the Vectra, according to their flow chart I have about 15' of head.
The Fluval doesn't even go that high and 15' of head on the Current USA pump is close to the same, maybe a little more flow.
The Fluval has a 1.25" outlet and the Current USA has a 1" barb outlet.
Not sure which would guarantee me more flow.
Brew12
Electrical Gru
New fittings should help. It really is like having a ball valve 1/3 of the way shut in your system. But at the low total flow you have this probably isn't have much of an impact yet.
I also want to clarify that the flex PVC may be a better option than what you had since you are replacing what are even less desirable flow restrictions.
Have you considered this one? Looks like you would get more flow than either of the 2 you highlighted but it does cost more.
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d2mini
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Nope, I missed that one. Checking it out now...Have you considered this one? Looks like you would get more flow than either of the 2 you highlighted but it does cost more.
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d2mini
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That one has 1.5" outlet. Makes sense it can flow more at that size, compared to 1" or 1.25".
So what happens when it hits my 3/4" overflow?
Reviews make it seem like it has a bit of hum to it. May not be the best choice for my particular application where any noise could be an issue.
Gah! So many variables. My head hurts. lol
So what happens when it hits my 3/4" overflow?
Reviews make it seem like it has a bit of hum to it. May not be the best choice for my particular application where any noise could be an issue.
Gah! So many variables. My head hurts. lol
Brew12
Electrical Gru
The 15' estimated head takes that current reduction to 3/4" into account. I wouldn't expect to get the full 1300gph from the pump curve but you should get much more than you currently do. Seeing as this would almost double your sump flow I would think the extra flow noise through the sump will drown out any hum.That one has 1.5" outlet. Makes sense it can flow more at that size, compared to 1" or 1.25".
So what happens when it hits my 3/4" overflow?
Reviews make it seem like it has a bit of hum to it. May not be the best choice for my particular application where any noise could be an issue.
Gah! So many variables. My head hurts. lol
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d2mini
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HA! Point taken.I would think the extra flow noise through the sump will drown out any hum.
Brew12
Electrical Gru
Any way you go, because of your flow restrictions, you will need a larger high pressure pump. These are inherently noise so it will be hard to find a quiet solution imo. Putting the motor on a sound dampening mat and plumbing it in with a soft silicon hose will help but it won't be completely quiet.HA! Point taken.
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If we can rely on the head loss chart for the SP6 it will not be adequate at all for what you need. Decided against the Deepwater Aquatics BLDC 15?
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d2mini
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Not completely against it, but two things were making me question it.
1) the large output size
2) reviews i've seen for customer service have been less than stellar.
Speaking of the output size, this is something that keeps confusing me and maybe I'm over thinking it.
But lets say we are looking at two pumps.
Pump A has a 1.5" output and Pump B has a 1" output.
Lets say my plumbing is 1".
Lets say both pumps advertise the same flow at 10' of head.
Will Pump B provide more flow at 10' than pump B because pump A was designed with a 1" outlet (same as my plumbing)?
I look at pumps like the BLDC that advertise a higher flow, but then I question that when I see it has a larger output that I can't really utilize.
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We would have to find out what size outlet was used for the flow rate and head height testing.
Like the Mag 1800 has a couple different head charts out there. One is with 1" pipe and another is with 3/4" pipe.
Edit: and that Jebao DCP18000 is a quick cheap test...
Like the Mag 1800 has a couple different head charts out there. One is with 1" pipe and another is with 3/4" pipe.
Edit: and that Jebao DCP18000 is a quick cheap test...
Brew12
Electrical Gru
The shape of the pump discharge is designed to the piping size connected to it. Once you get around 6" of length away from the pump the piping size only counts as head loses.
Pump A 1.5" output with 1' of 1.5" pipe and 9' of 1" pipe will be the same flow as Pump B 1" output with 10' of 1" pipe. Assuming of course that the pump curves are accurate.
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Yep, and some have shown them not accurate in one way or another.
I really want to get my hands on a SP6 as I'm hoping it's max head is actually higher then what's listed. It is a nice pump and great flow but at very low head heights according to it's rating.
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