Which draws more power...

[Anonymous]

An ampmaster 3000, or a Mag 7 and a Mag 9?
According to marinedepot.com, a Mag 7 draws 70 watts, and the Mag 9 93 watts for a total of 163 watts. If an ampmaster 3000 was really running at 1 amp, IIRC it will be drawin 120 watts (I could be so wrong).
So, I should repace the mags with an ampmaster and save myself 63 watts a day.
I am a little confused. Help!
:mrgreen:

 

[Anonymous]

Look at the electrical formulas here.

The Pump Selection Guide here at RDO does not show watts or horsepower for the Ampmaster 3000. Where did you get that it draws 1 ampere?

If 1 ampere is correct, then you still need the power factor of the motor to accurately calculate the watts. Lets assume a 85% pf and calculate the watts. W = E X I X pf. W = 120 X 1 X 85% = 102 watts. Somehow, this doesn't seem right for that size pump. Where did you get that 1 Amp from again?

Louey

 

[taikonaut]

Ampmaster's full load amp is 1.3A, but most situation, it operate between .8 to 1.1 A. See Premium Aquatics page, for example.

For an external pump like Ampmaster, it is more efficient due to the engineered impeller. For the Mag pump, the impeller can spin in either direction (not unidirectional), and the efficiency suffers.

 

[npaden]

When people have actually tested the Ampmasters for actual power consumption they have ended up being quite a bit higher than the manufacturer's claims. You might try a search but IIRC they were in the 200 watt range. Not bad for that kind of flow, but if your goal is purely to save a few $ of electricity even at 63 watts savings at 8 cents per kwh that is only $44 per year. Would take a few years to pay that new pump off at that.

I would just stick with what you got unless you are wanting to bump up flow or something, but switching purely for the power savings isn't going to math out.

FWIW, Nathan

 

[Anonymous]

Thanks guys, I always struggle with electrical.

I got the 100 watts thing from a post somewhere that said 1 amp = 100 watts.

 

[taikonaut]

That's right if the voltage is 100 VAC without the complication of powerfactor that Louey mentioned.

 

[REEFKEEPA]

If you are really concerned about a small load such as 100 watts, it may be time to run a new circuit to your aquarium. If you are maxing out your current C.B. rating you are flirting with disaster.The easiest way to tell how much current is flowing through a circuit is to use an Amprobe at the panel with everything on that particular circuit turned on. If you are within 80% of the C.B. rating you should be fine. Anything above that and I would run at least one 20A circuit to the tank location. 2 would be better.That way if one breaker trips the other one will still be on line.

 

[Anonymous]

Just to make things more confusing, remember, the greater the head pressure or resistance, the less energy will be consumed.

 

[Anonymous]

I am not concerned about the load. I am worried about 100 watts because if I don't have to be using them I rather not. I alread have two dedicated circuits for my system.

I have an extra ampmaster laying around, so I thought I would ask.

Gonna stick with things the way they are for now.

Thanks for all the replies.

 

[Emperator]

Just to make things more confusing, remember, the greater the head pressure or resistance, the less energy will be consumed.

i thought it was the other way around. hmm.

 

[Anonymous]

Pump hp is

(HQ(SG))/3956

H - head in feet
Q - flow in GPM
SG - specific gravity
3956 - to make the units work

TO find the power needed you ned the eff of the pump and motor. If you know the eff of the pump the equation becomes

(HQ(SG))/(3956(EFFpump))

EFF pump - pump efficiency

THis gives the required hp to drive the pump. To find the power needed to run the motor. Take the pump Hp and divided by the motor eff

Hp/EFF motor

Sorry for the neard out. I'm studying for the PE and I am in the middle of hydraulics. I workd some of these types of problems last night.