Eheim Pumps Rated Wattage False?

[CThompson]

A week ago, I had the loan of a "Tong Meter" which checked on the actual wattage used by electrical equipment.

I checked most of my fish tank equipment, to work out the watts they actually used. I expected to find a little bit of variation, which I did. But, what has surprised me the most is when I checked my Eheim 1060 and Eheim 2260 Hobby Pumps (both operated at zero head).

Both have marked on them that they are a 50 watt pumps.

My meter rated them each at 96 watts .

That is a big difference.

I have always though Eheims are good pumps, good for their reliability, their silent running, and - their low wattage. I have always felt that their initial high purchase price (and cost of replacement parts) were offset by their low cost of running. However, with the reading I had returned on their true cost of running, this "balance" (purchase cost verses running costs) for me has been altered.

These Hobby pumps can be a bit limited if you need to move some water in a vertical direction, however, provided you run them within their abiltites, their reliability, quite running and cost of running I have always felt made up for this. However, if in fact their wattage is incorrectly rated, and they are virtually double their stated wattage - perhaps they are not as good as I have always understood them to be.

My meter wasn't able to check on electrical equipment of too low a wattage, so I couldn't check my Eheim 15 watt (?) 1048.

Can others who read this, if you have equipment to check, could you please check the wattage on your Eheim pumps, and please verify or refute wether your Eheim Hobby pumps (or other Eheim gear) are using the wattage they are rated at, and post back.

I would like to know if I alone have this problem, or if indeed Eheims are sold under false pretences?

Craig

[Lee Miller]

Craig,

Is this not a provocative statement?:

...or if indeed Eheims are sold under false pretences?

I would like to see how Eheim quote the wattage of their products. Is it as the power produced by the motor or as the power consumed to produce the claimed performance?

If I was to purchase a motor vehicle that the maker claimed to have a 100kw motor and it actually produced 200kw I think I would be happy (I belong to the 'No substitute for power' brigade!).

Therefore, if an Eheim motor was capable of producing almost twice the advertised (rated?) power, couldn't that be a good thing?

Regardless, any electrical motor, whether it’s running a pump or any other device, is going to have a certain power consumption when running without a ‘load’ (bearing friction, air resistance to the cooling fan etc). The load (or resistance) applied is going to increase the power consumed and therefore the running costs.

Is it possible that Eheim have rated their pumps as having 50 watts of available power? (after losses due to friction etc). Again, that would be a good thing and a responsible way of rating the pump.

Theoretically, the power needed to move ‘X’ volume of water to a height of ‘Y’ metres in ‘Z’ seconds can be calculated. Theoretically twice as much power will be needed to move ‘2X’ volume of water to a height of ‘Y’ metres in ‘Z’ seconds and so on.

If two or more suitably sized pumps were asked to do the same job then, theoretically, the only differences in power consumption would be due to the efficiencies of the motor/pump themselves. We then get into matters of increased efficiency (possibly lighter-weight construction) versus reliability and longevity. Most things in life are trade-offs.

Eheim, generally, have an excellent reputation for products that are reliable and long-lasting.

“…false pretences…” it appears that the product may be under-rated rather than over-rated, and possibly with good reason. Hardly false pretences.

Just my view.

Lee.

[Ash]

but with equipment like this Lee, it is thought of as having a lower power consumption than the "cheaper" brands - so really the car power analogy is inappropirate as it isn't "grunt" that people look at pump rated wattage for, they view it as a measure of economy.

picture buying a Prius over a Corolla because you think the advertised running costs of 5.5-6l/100km will give you longer term ecomomy - yet it in actual fact gets 10l/100km!*

Wouldn't you be upset that the stock corolla could have done the same job with cheaper running costs & cheaper purchase price?

I think this is what Craig is getting at

Disclaimer * these figures are purely fictional & used in a context to form an analogy between cars & aquarium pumps.

[Lee Miller]

Hi Ash,

My car analogy was only to suggest that maybe Craig was getting more than he thought he was getting.

That's also why I asked how Eheim rate their power - as output or consumption - and then went on to draw attention to the fact that the only real difference in power consumption between an Eheim pump and any other brand doing the same job would be in the actual efficiency of the pump.

A pump with a rating of 50 watts isn't going to use the full 50 if the job only requires 20.

I hope this clarifies my point(s)

Cheers

[CThompson]

Hey guys,

Leave car analogies out of it – you’ll just confuse me.

When I read that a pump has “X” wattage – at what ever LPH, I will assume that the X wattage will be how much power the pump will use to produce its flow rate, and following on from that, what the pump will cost me to run.

If I have a pump, and it has “X” wattage at “X” LPH, I expect it to do this rate of flow at this wattage.

I expect I will loss this flow rate if I have the pump working at head, but I still expect it to be somewhere near the rated wattage. Perhaps it may increase if I am making it work really hard, (bearing in mind I am no expert on electrical appliances), however if a product is rated at using a certain amount of power, and producing a given output (flow rate), then if I ask it to produce the flow rate the pump is sold for, then I will expect it to also do so at the wattage rate it is detailed at requiring.

I don’t expect to have nearly doubled the “X” wattage of the pump, for the same flow rate. That is, if the pumps draws nearly double the wattage it is rated at, am I getting nearly double the flow rate? I don’t think so.

The two pumps in question that I tested, are both operating at zero head (plumbed into the bottom of the tank – inlet and outlet). Both pumps are detailed as requiring 50 watts of power, both pumps were taking 96 watts.

I see this as false advertising (unless both my pumps are faulty though neither is particularly old, and it seem rather coincidental that they were both faulty at the same wattage), with the manufactures making their pumps seem more efficient than other brands – which I have always though Eheim were.

I would like to find out if other Eheim pumps out there, are also drawing their rated wattage capacity?

Craig

[CThompson]

A pump with a rating of 50 watts isn't going to use the full 50 if the job only requires 20

Other way around mate. If a pump is rated at 50 watts, then I expect it to draw something near this to produce what it is manufactured to provide. And not to draw nearly double to produce the same rate of flow at what it says it can produce with 50 watts.

I can't ask it or cause it to produce less water flow, if I could then perhaps I may expect to need less watts to do so. However in this case the flow rate is set by the manufacture, and they state it will do so at wattage in this case of 50 watts.

If a pump is not using 50 watts, and instead is using 96 watts, what does this tell you?

Craig

Ash - you understand what I am getting at, thanks.

[OziOscar]

I could be wrong but...

I understand what you're saying - you're expecting to only spend (50W x 24hrs x 7 days x etc) on power and you're up for almost double that. A lot disappointing.

Some of the mini-servo motors in the machinery here draw a lot more power when they are not loaded (ie gear head not engaged, etc). Put the gear-head on so that they have a load and the current draw drops quite a bit. eg No gear head, motor makes 8000+ rpm. Gear head on, motor makes only 3000-ish rpm (at the gear inserted into the gearhead, not at the output shaft). This is ignoring the high start current, as for any inductive load.

Maybe the pumps are spinning very quickly because of no load (ie zero head, short pipes, etc) on them and therefore consuming more power?

I'm no engineer so am just guessing.

Cheers - OziOscar.

[r.d.m]

id guess that eheim rate there power consumption dry or totally immersed with no load, as there are so many variables(head height etc) a bit misleading id admit ,it would be interesting to check other household appliances , but i think an email to eheim would be in order in the words of a red haired ex politition"please explain"

[CThompson]

id guess that eheim rate there power consumption dry or totally immersed with no load, as there are so many variables(head height etc) a bit misleading id admit ,it would be interesting to check other household appliances , but i think an email to eheim would be in order in the words of a red haired ex politition"please explain"

←

I have sent the following email to the contact page on Eheim's web site;

I recently tested the wattage of Eheim hobby pump, 1060 and Eheim hobby pump 2260, both rated at 50 watts.

Both pumps are plumbed inlet/outlet via bulkheads into the bottom of a tank, so they are operating at zero head.

I tested with a tong meter, and both pumps returned a wattage of 96 watts each.

Can this please be explained to me?

Craig

[Ash]

do you have any similar rated wattage/LPH resuns or pondmasters or something? Just another pump being utilised at 0 head as a comparison

[teflon]

I have never been a fan of this brand anyways, The way i see it is that people think because they are buying a pump that costs 4 times more then another that it must be better, I also think if resun was more expensive and claimed to be made in Germany it would be all the hype.

CThompson im pretty sure thats classed as "False advertising" as they claim to use 50watts but use almost double that. Its pretty much like a having a bank thats says they charge you $5 a month for fees but in actual fact they are charging you $10.

I also dont see how a pump could only use 20watts if its a 50watt pump I have always been under the impression that you couldnt alter an electrical device's wattage if it is fixed.

I hope you get this sorted CThompson as I personally think its wrong.

Good luck

Cheers

Adam

[Ash]

I thought maximum wattage was relatively fixed, but if the unit was under less strain it would draw fewer amps & therefore use less watts? (refer the heater thread)

Depending on how they rated the pump at 50W it may not br "false advertising" - misleading if you take the reading out of their tested context perhaps - but not false

what does the Eheim manual say regarding these pumps & their ratings?

[BaZ]

Perhaps the motor was rated while spinning freely on a test bench without any water to push through long skinny hoses.

I see why you are questioning though Craig. I too have purchased pumps based on their low power consumption (I hope) compared to other brands, so I would be disappointed to learn that they drew as much as the cheaper models

I understand Lee's argument for wanting a powerful car, but I don't think he wants to tow a caravan with these pumps mate

How does a tong meter work Craig? Are they hard to use and hard to get hold of?

[Matthew]

G'day Teflon.

Resun is a company that appears to build products that closely resemble others that are already in the market place.

Their cost is often a substantial amount less than say an eheim, but I have an eheim that I bought second hand, it is at least 15 years old. I have never replaced the impeller nor have I had any problems with it. However every other pump or cannister I have, has consumed multiple parts or in a lot of cases simply died.

It all comes down to how long you want the pump (or whatever) to last. If you are only in the hobby for say 12 months then often these items will be perfect but if you want them to last say 15 years plus, then I would be buying an eheim.

Buy whatever you feel is the best balance for your needs.

**************

G'day Craig

My first thought was is the "Tong" calibrated?

However I assume you tested other appliances so if they were roughly what they should be then perhaps the eheim units are erroneous?

It will be interesting to see what information comes back from eheim.

cya Matthew

[Lee Miller]

Craig,

I originally said:

I would like to see how Eheim quote the wattage of its products.  Is it as the power produced by the motor or as the power consumed to produce the claimed performance?

A manufacturer should be able to guarantee the output (or available power) from its products. If a manufacturer rates a product at a certain level and manages to exceed that level then isn't that a good thing?

It appears to me that you have taken the position that Eheim has provided a power consumption figure, is this how it promotes its products?

I think it's rather unfortunate that the term 'watt' is used to describe both the guaranteed output of a device and the amount of energy the device consumes to provide that output. For the remainder of this topic I will be using the words 'grunt' and 'juice', where:

grunt = the amount of power produced by a motor

and

juice = the amount of energy consumed by a motor

My argument goes; if Eheim write on the side of their box that the pump produces a grunt of X and it actually produces 2X then I'm in front because I can safely use 1.5X of the available grunt to do what I want to do. But obviously, if I'm using 1.5X of the available grunt I'm going to use more juice.

Whereas, if Eheim says that its pump will use X juice to move Z litres of water @ Y head and it actually uses 2X juice then I'd be within my rights to be disappointed.

From my searching of the Eheim website I can find information on flow rates Vs head but no information on grunt or juice.

Additionally you state:

Both pumps are plumbed inlet/outlet via bulkheads into the bottom of a tank, so they are operating at zero head.

‘Head’ of water is a means of measuring pressure. 1 metre of head = 9.8 kpa. I’m not sure how you get ‘zero’ pressure at the outlet of a pump. Even if the inlet and outlet were connected to each other (water in = water out) there would still be pressure due to friction in the pipe. It is my opinion that there has to be some pressure that the pump is working against and this is obviously going to affect the juice consumed.

Cheers,

[OziOscar]

I think that this LINK explains this somewhat - especially the "Motor Load" section. This LINK also explains it too, albeit while trying to push the idea of variable frequency drives. Sorry - you're going to need to extrapolate a little with some of this really dull tech info.

I did read something about this characteristic on (I'm pretty sure) the Grundfos site as we use some fairly large Grundfos pumps in our facility (work, not my humble aquariums!) and there were huge differences in the electrical consumption depending on the piping configuration and the position of the bypass valves (industrial chillers for injection moulding machines) ie backpressure limiting pump rotational speed.

And dare I say it - the voltage was higher or lower than 240VAC at the time, this would also have an effect on the power consumption. Despite our faith that we're getting 240 all the time, the data loggers on the inputs on our stabilisers and UPS systems (>80 kVA each) show anything from 200 - 280 VAC on each phase at different times of day for either short or sustained periods. This has a dramatic effect on the power factor (which is a whole other kettle of fish I just am not getting into).

I hope we can get to read the response from Eheim if and when they respond.

Cheers - OziOscar.

[Colfish]

hi Craig

you say these pumps are connected via bulk heads to the bottom of the tank, and therefor running at zero head pressure [???]

if the tank is FULL, i'd be of the opinion that those pumps are pushing at a very high head pressure. therefor using all the 'juice' available to produce maximum 'grunt' to move the stated volume.

we all await Ehiem's reply.

cheers

[Ash]

Question for Lee - why would they rate a pump by it's output equivelent of electrical energy when it's output is water?

If it was a water wheel producing electricity this would make sence.

if the output of the pump in watts is 50W whilst it's drawing 98W - is that 48W lost going into heat in the tank? It has to go somewhere.

I think rating a pump by it's energy consumption on the "input" & it's fluid throughput on the "output" is much more logical, in which case these pumps are using roughly twice that which they are rated to use.

[CThompson]

Perhaps the motor was rated while spinning freely on a test bench without any water to push through long skinny hoses.

I see why you are questioning though Craig. I too have purchased pumps based on their low power consumption (I hope) compared to other brands, so I would be disappointed to learn that they drew as much as the cheaper models 

I understand Lee's argument for wanting a powerful car, but I don't think he wants to tow a caravan with these pumps mate 

How does a tong meter work Craig? Are they hard to use and hard to get hold of?

←

I work at a scientific organisation, and I got one of the technical gurus to rig me up a short (40cm) extension cord, with one of the wires exposed. I plugged the Eheims into the power socket via this modified extension cord, then hung the hook off the tong meter around this exposed wire (if that sounds dangerous it is not). It was just a matter of multiplying the resulting reading by 240 (the volts), to get your wattage.

I have no idea as to how available tong meters arethey are, but I'd imagine if you were employed in the field of electronics, or perhaps an electrician, you may have access to one. I understand there is other equipment that can do the same sort of job though.

Eheim's drawcard to me is their reliability, their quiet running - and importantly their low wattage ($ to run). This low wattage in my mind helps to make up for their cost of purchase. I understand that it is possible to buy replacement impellors, and their cost is greater than the entire purchase of another brand of pump. Buy hey they're Eheim, and cheap to run....doh!

Seriously, though I would like to find out if my two pumps are the exception or the rule

Craig

[Skyedge]

Craig,

You have brought up an interesting topic, as I am an Eheim fanatic myself.

I have the same opinion as Colfish, that the pump is working harder to produce the same juice..(ha..ha I like the juice and grunt analogy), because it will have presure from the water in the tank while pushing the water onto the tank from it's outlet.

Would like to see Eheim's response on this..

[CThompson]

Craig,

I originally said:

I would like to see how Eheim quote the wattage of its products.  Is it as the power produced by the motor or as the power consumed to produce the claimed performance?

A manufacturer should be able to guarantee the output (or available power) from its products. If a manufacturer rates a product at a certain level and manages to exceed that level then isn't that a good thing?

It appears to me that you have taken the position that Eheim has provided a power consumption figure, is this how it promotes its products?

I think it's rather unfortunate that the term 'watt' is used to describe both the guaranteed output of a device and the amount of energy the device consumes to provide that output. For the remainder of this topic I will be using the words 'grunt' and 'juice', where:

grunt = the amount of power produced by a motor

and

juice = the amount of energy consumed by a motor

My argument goes; if Eheim write on the side of their box that the pump produces a grunt of X and it actually produces 2X then I'm in front because I can safely use 1.5X of the available grunt to do what I want to do. But obviously, if I'm using 1.5X of the available grunt I'm going to use more juice.

Whereas, if Eheim says that its pump will use X juice to move Z litres of water @ Y head and it actually uses 2X juice then I'd be within my rights to be disappointed.

From my searching of the Eheim website I can find information on flow rates Vs head but no information on grunt or juice.

Additionally you state:

Both pumps are plumbed inlet/outlet via bulkheads into the bottom of a tank, so they are operating at zero head.

‘Head’ of water is a means of measuring pressure. 1 metre of head = 9.8 kpa. I’m not sure how you get ‘zero’ pressure at the outlet of a pump. Even if the inlet and outlet were connected to each other (water in = water out) there would still be pressure due to friction in the pipe. It is my opinion that there has to be some pressure that the pump is working against and this is obviously going to affect the juice consumed.

Cheers,

←

Lee, sorry mate, your grunt and juice "don't" help. When it comes to the ins and outs of electricity, call me Cat weasel. I know you have a point, but I don't understand it. My simply understanding is that the pump has a 50 watt power consumption. For example, if I wanted to connect this up to a UPS, I would use this rating to understand how long a battery would last (for the battery size). However, when tested it had wattage of 96 watts, and not the advertised 50 watts.

I stand corrected; yes I agree there will be some friction in the pipes, so the head will not be zero. However, the runs of tubes are very short, and will be negligible, or should I say they can't affect the amount of power the pump consumes as this is fixed. The only difference I should have is in the output of water from the pump. And even if this output was dramatically reduced by head from height the pump has to move the water, or head from friction inside the pipe, I still can't affect the wattage it uses.

Is this correct?

Juice = power consumption

grunt = the amount of head

If so, then I would still say, the wattage is fixed. If I have the pump working harder, the power consumption would still be fixed, but the output from the pump would be reduced?

Craig

Craig

[CThompson]

hi Craig

you say these pumps are connected via bulk heads to the bottom of the tank, and therefor running at zero head pressure  [???]

if the tank is FULL, i'd be of the opinion that those pumps are pushing at a very high head pressure. therefor using all the 'juice' available to produce maximum 'grunt' to move the stated volume.

we all await Ehiem's reply.

cheers

←

G'day Colin,

I understand your point, but no, they are operating at no head (head as in hight to pump the water Lee). If you take a siphon hose, put one end into a tank, and start the siphon from the other end, and let the water fall into a bucket. Now pick this loose end up and raise it above the level of the water in the tank (where the water is being siphoned from). The water level in the hose, where the water stops in the hose is the same height as the water in the tank. If you want to move water beyond this point, this is the head height the pump has to move the water, as gravity will make the water to equal the water height in the tank.

If I had a pump plumbed into a sump, pumping water from here to the top of the tank, then the head height would be from the water level in the sump, to the height beyond this the pump has to move the water.

If I had this same pump plumbed inlet/outlet via the bottom of the tank, there will be no head "height". As Lee points out though, there will be head caused by the friction from inside the pipe, but this is a different type of head, and not as impacting as head friction. This is why the shorter the tubing you have the better off you are.

I trust Lee, that you will agree with this?

Craig

[marls]

Hi Craig,

Just my 2cents worth....

Basically all electrical appliance will state their max. power consumption... eg 50W. This means that that device will consume a max. of 50W and should not exceed that......

Power consumption ratings are actaully regulated by Dept. of Fair trading Office - Electrical safety department...... I suggest that you contact them if you any queries regarding your appliancies power rating.

I hope this hepls.

Cheers

Marls.

[Ash]

I'd wait for Ehiem's (or perhaps the retailers?) response before getting Fair Trading involved

[CThompson]

Thanks for your comments Marls and Ash.

In order of preference;

1. I would like to hear if others, after testing their Eheim pumps have similar issues.

2. I'd have a response back from Eheim.

3. If there is an issue with the pumps wattage, I'd like others to be aware.

Then possibly I may take it to the Department of Fair Trading.

Eheim make a lot out of their name built upon their equipment's reliability, their quite running, and their low cost of running. I certainly have recommended them for years, and I have a lot of Eheim canister filters, and their hobby pumps. If one of these three things (reliability, quite and low running costs) is not as advertised, this needs to be understood to make purchasing decisions.

They may still make a better pump, and a customer may still purchase it, but you need to correctly understand what your purchasing decisions are based off.

Hasn't anybody got some equipment to test the power consumption of their gear ?

Craig