Dolphin Ampmasters

[SuperFudge]

Hi,

I currently have some 1/2 horse jacuzzi pumps,wich are rated at aprox 45 gpm,and draw about 4 amps each........i have read abit about the ampmasters drawing a max of between .8 to 1.8 amps max at only 1/15 horse,and almost matching them for volume.

I have heard that these specs are not exactly true as far as true power consumption for the dolphins,is this possible without being false advertising ?

Could any of you electricians enlighten me?
As i wish to purchase one in the near future.

Thanks,Marc.

[titus]

Hello,

Actually Darren you have the meter to test for power consumption, right? Maybe if you don't mind and have the time to clear this thing up since you have the Ampmaster running?

But I agree with your doubts too. The Emerson motor on the Ampmaster is identical to my 1/3 HP on my table saw. Now the table saw motor is about 5 times more powerful but is a 15A motor. So even 15A/5 = 3A. I know things probably does not follow a linear relationship but 3A is quite a bit high compared to what the Ampmaster is rated at and it's identical motor brand and housing and such.

[DJ88]

I'll hook it up today and see what I come up with.

didn't even think about trying it.. lol..

oh wait.. I'll hook all the plumbing back up n fill the sump with water first.. then run the pump.. lol

[Troy F]

I bought one on Saturday to run a closed loop I'll be looking for some opinions on plumbing it in Darren.

[DJ88]

Marc Titus,

One thing to concider with these pumps is that they run at a lot lower RPM than a table saw is required to run at. But then again you use various pulleys to increase the RPM there. The housing and such isn't a good indication of how the inner parts of the motor is set up. You will need to know how many windings and such there is inside.

Titus,

If you take a look at the CSA manufacturers plate on the side of the motor itself you will see that the max Amperage is 1.3A. And it's RPM is 1725. I highy doubt a well known manufacturer of motors such as Emmerson will falsify these numbers to CSA.

I can see the wattage numbers being different but not much. If you multiply out the Volts and Amps on the side of the motor you get 149.5 VA(Volt Amps). This is usually not equal to Watts. Unless it is a perfectly efficient system with no resistance or inductance(which for the most part is impossible). With this being a motor tho it should be almost 100% efficient. So you could say that VA is very close to Watts.

In a nutshell I'll put money on this pump drawing 150W like they say. Or very darned close to it.

I'll test it a bit later with my transducer to make sure. Have to re-wire it a bit.

[ 20 May 2002, 12:12: Message edited by: DJ88 ]

[Mushroom Boy]

Have you had a chance to test this yet Darren? Inquiring minds want to know :D .

Paul.

[DJ88]

Here is the numbers.... Not good....

With a load(ie pushing water) here are the results.

at initial startup. Motor draws 2.8 amps (RMS) after five minuutes it dropped to about 2.0 amps. (RMS) Not the 1 amp quoted. Not even close.

According to Dolphins website the pump's current draw will decrease as the head pressure goes up. Well I never even got down to the highest amperage they quote.

As for wattage consumed. Here is another kicker..

At initial startup 244Watts 120VAR's.

after 1 min 230Watts 106VAR's

after two min 226Watts 103VAR's

after five minutes 222Watts 101 VAR's

I kept measuring beyond five min but it leveled out at 222-224 Watts.

Hmm Me feels like I was taken for a ride now..

all measurements were done with a WATT - VAR transducer and a fluke 87 series III multimeter.

If anyone wants the accuracies/error factors of the meter or transducer let me know and I will get them for you.

I'll just say the error factor on both is under 0.1%

:mad: :mad: :mad:

I am going to go take a few deep breaths.. see ya later.. ;) :D

[ 24 May 2002, 13:43: Message edited by: DJ88 ]

[DJ88]

As an addendum. I am running my entire system with 1.5 " PVC. Not reducing the tubing anywhere.

[DJ88]

Talked to Tom Briscoe Jr. at Dolphin just now, thanks Troy for using your dime. :D and it turns out we are both right, kinda.

The wattage consumption that Dolphin is claiming is what the motor actually draws if you test AT the motor. Not at the wall. The difference in wattage is due to line losses from the motor to the wall. So in effect we are BOTH right. The motor uses 150W but from the wall 222Watts is used. The wattage difference between the two is lost due to resistances in the wiring from the wall to the pump motor.

I am betting that you will find this with all pumps and equipment sold to the hobby. I am going to test Troy's MAK4 in a few minutes just to find out for sure.

Talk later.

[ 24 May 2002, 15:02: Message edited by: DJ88 ]

[StirCrazy]

Hey Darren, this is a interesting result. let me see if I get this right.. the aquarium pump manufactuers are rating the power like that to make it look better than a .. oh say a hot tub pump that is rated the same but 1/2 the price?

am I thinking along the right path?

Steve