Float Switch turning OFF Return Pump?

If you could, this is what I would do, drill a hole near top of the sump, install a bulkhead and a hose/pipe, place a small empty tank/bucket close to it. When water in sump raises up to the bulkhead, it will drain into the bucket. This is safest way imo, forget about the switch.
 
I use a reed switch which activated by a tiny magnet. So if I let the magnet gets close enough to the switch, they will stick togehter, keep the circuit open once the siphon happen 'til I start manually restart the circuit.
Material:
_a low voltage SPDT relay
_an adapter
_a reed switch (local RR stores sale the smallest reed swithces)
_a float
_something to hold the float and the magnet
Voila cheap and safe
Hope this help:)
 
<a href=showthread.php?s=&postid=7960980#post7960980 target=_blank>Originally posted</a> by BeanAnimal
Driftwood, it is a HUGE deal. The ups output bus in simply not designed to handle the load signature of a motor. The "modified sine wave" radically changes the way the motor operates and this in turn puts a tremendous stress on the output devices (transistors) in the UPS. This can EASILY result in damge to the unit and/or fire.
Bean

I am the guy that does his own reaserch and hangs up on people like you when they call. I have a degree in computer electronics and am not dee dee dee.

Most AC motors - power tools, for instance - will run OK from modified square wave power as well, but they're likely to draw about 20% more power than you'd expect, and may buzz annoyingly. Things with circuitry that relies on clean sine wave power - electric clocks, bread makers, some battery chargers, the "shaded pole" motors used by ceiling fans - are likely to misbehave. Some fans with synchronous motors may slightly increase in speed (RPM) when powered by an inverter. This is not harmful to the fan or to the inverter.

Some AC motors will even run on a square wave.
 
Lets get a few things straight here bub... We could have had a polite conversation... but it appears that you would rather take a more smart alec stance. Oh well.

1) I don't "call" guys like you. YOUR GUYS CALL ME. I design infrastructure and implement it, not "sell it". The technology is my expertise, not the sales. Your the "know it all type" that I have to deal with every day.... You got an IT degree and learned about computer electronics and think your a power expert. Your the guy whos "recomendations" caused the last big outage that prompted your boss to call somebody who knows what they are talking about. Good grief.

2) What does a degree in computer electronics have to do with anything? You sure don't seem to know much about power systems, which is what we are talking about here.

What begs those harsh remarks? You tout yourself as being a computer electronics expert, but show the exact opposite. You do not demonstrate more than a working knowledge of power systems and UPS/INVERTER technology. [SIC] "I use a small computer ups to run my pump" Give me a break: Even not "computer electronics" guys know that your remarks are silly.

3) MOST AC MOTORS and POWER TOOLS don't fit into the same sentance driftwood. One is a Universal Motor (power tool) and the other is an INDUCTION MOTOR. Hand drills, rotozips, routers, jigsaws, circular saws, etc... all use universal motors, that is why you can easily control their speed. Table Saws, Drill Presses, Ceiling fans, air conditioners, pumps, fans, etc all use INDUCTION MOTORS: You control their speed via PWM, FREQUENCY, or fixed winding sets. You may want to do some research before you step off the deep end. I am not going to waste time explaining why the UNIVERSL MOTOR does fairly well on a step wave or square wave... you can find that information any of a thousand places. The point is your premise about what devices fit your example is dead wrong. MOST MOTORS DON'T work with a poorly shaped waveform!

One more time in case:
You mention "shaded pole motors" and cieling fans... Let me breaks some news to you. A shaded pole motor IS an induction motor. What exactly do you think MOST pump motors are?

And lets hammer it home:
Here is a hint.... if it has BRUSHES it's a universal motor... otherwise it is an INDUCTION motor (shaded pole or split phase) motor. Such motors (induction) rely on a clean sine wave. A square wave produces less torque between the peak and zero crossing voltage. The motor lags behind and the saturated field becomes a dynamic brake for a portion of each cycle. This not only heats the motor and puts the insulation through a LOT of stress, it can quickly cuasing insulation breakdown and grounding.

In addition: this "dynamic breaking" causes a very complex load to be presented to the output devices on the inverter. They are no longer supplying a simple continuous load with a saturated field. The outputs are now trying to keep up witha very dynamic load that appears to change in resistance and amperage several times a second. MOST UPS outputs are simply not designed to handle this.

Remember Mr computer electronics degree... most of the inteneded desktop UPS equipment runs off of a switch mode PSU that could care less about it's input waveform. The current draw is somewhat low and the surge currents are not very high. The output devices on a typical desktop UPS are not heat sinked or paralleled for duty anywhere near what a MOTOR will put on them.

Now driftwood... do you want to talk about inverter output technology? Do you want to talk about the differences between different UPS technologies?

Here is another hint:

A desktop UPS uses BUCK/BOOST to maintain the output voltage. Do you know that is? Can you please tell me what it does to the waveform on the inverters output?

Here is another hint:
As the motor heats up and lags furhter behind, the current draw will increase. The current increase causes a voltage decrease on the UPS output. This puts the BOOST circuit into play, which further degrades the waveform in an attempt to keep the voltage up. Remember Mr computer electronics... the UPS is designed to provide VOLTAGE to the switch mode computer PSUs... they don't care much about waveform.

It is much cheaper to design a BOOST circuit than it is to design a backend UPS bus and battery management system that can adapt to voltage swings and maintain a sine wave on the output.

If you are open enough to learn about power systems and UPS technology, I would be more than happy to provide you with plenty of information. On the other hand, if you think you know it all (which is very obvious that you don't)... well then keep hanging up on people and tell yourself you know it all.

But lets get back on track here driftwood:

Pleae post the exact brand and model number of the UPS you are using. Pleae post the make and model of the pump. And by all means please post the how much RUN TIME you get from that pump on that UPS.
 
I would never say that I know it all. It is my job to understand a little bit about alot of different things. I am not the know it all type and I am not the 'IT Degree' reject either. I built a 12v inverter to run my CB radio when I was 10 years old. Sorry you took offense to my remarks, I was joking.

Your comments about how it would EASYLY cause a fire didn't sit right with me and I did some research. Many others say that an AC motor will run alright on a modified sine wave. No mention of fire or any danger. Those comments in my post were copy/pasted from two different websites. I am by no means a UPS expert, you obviously are. But I do know quite a bit about electronics, and did way before I ever went to college.

Myself I use an APC 1500 running a Maxi-jet 900. I haven't had to test it yet, but with the maxi using 8.5Watts it should last quite a while.

I really didn't want to start a war with you over this. This site is here so people can help each other. I honestly thought you were trying to scare the guy.

I would still like to see some documentation that says an AC motor or the cheap UPS running it would catch fire in this situation.
 
Lets take a step back then...

Apology accepted.. and I offer one likewise. If you were joking... I read it the wrong way.

With regards to the facts of the matter:

I WAS trying to scare the guy (and you... and anybody else who wants to plug a pump into a UPS). The potential for fire is real and depends on how gracefully the UPS deals with overloaded outputs. Because the overload is not a simple "overcurrent" many times the breaker or overcurrent protection does not trip. Instead the output devices get hot and melt or burn. Similar to shorting or overloading the outputs on a power amplifier (though in the most basic sense a power amp provides CURRENT and an inverter provides VOLTAGE... thats not relavant here)

The only thing you need to understand is that the cheaper the UPS, the worse the waveform and the lower the quality and engineering of the output devices. (Those APC units are OK for SOHO desktps and such.... they don't fly to far in enterprise situations).


Your MJ draws a very small amount of power, but is also a rather "crude" motor topology. It will likely work ok on a 1.5 kVa ups like you have. However it may not "start" under battery, so as long as it is spinning during the mains to DC bus switchover, it will likely stay spinning.

On the same token, plugging a MAG 7 into the same UPS is likely to cause some funny sounds and smoke.

Thanks for the level headed reply... and take care :)
 
My APC UPS does have a sine wave output, not simulated sine. I will have to do some testing with it on battery. I have a mag9.5, not on the UPS that is 19Watts. I read that starting wattage for a motor is 5-7 times the normal usage. 19x7 is only 133, shouldn't the APC be able to handle almost 1000 watts? If I am understanding this wrong, please correct me because I was thinking about a second 1500 to run that mag and keep my sump going in an outage.

Just out of curiosity I dug out a manual to a cheap simulated sine 'cyberpower' UPS unit like the one SA057 is probably using. It has a bunch of caution statements, including one about aquariums and condensation. There isn't anything on there about motors causing it to potentially catch fire. I'm not trying to argue, I just don't quite believe you yet. :) I know, I'm stubborn, but I tend to be quite skeptical of anything until I can confirm it in more then one place.

Both of the reef podcasts I listen to recommended to their listeners that they get a UPS and connect it to at least one of their pumps to keep water movement going in the event of an outage. They even said to go get a cheap desktop UPS if you couldn't afford a real one. If there is a real danger someone should let them know so they can edit those episodes and let their listeners know.

Thanks!
 
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<a href=showthread.php?s=&postid=7963630#post7963630 target=_blank>Originally posted</a> by BeanAnimal
If your going to drill a hole for a bulkhead and overflow can, why not just use it for the return? Kinda silly.
The problem is that his stand may not have enough room for extra tank so it has to be outside, that is why I said SMALL EMPTY tank or bucket that enough to fill drained water. Why silly?
As I re read the post, he is worry about losing siphon in the U tube which could overflow the main tank (not the sump) if the pump is not shut down, so this does not apply to his case.
He may want to mount a float switch near top of the main tank or in the sump (1-2" bellow water level in reverse). Of course, this could cause the pump to cycle on/off but won't overflow the tank or the sump
 
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Instead of coming up with all this stuff, why don't you just address the root cause and either drill it or take it somewhere to get drilled.

30g tank is not the end of the world to temporarily house your livestock in a tub while you drill or take it to get drilled. We aren't talking some 500lb monster that have to get 5 guys to move the thing. Take your lumps and do it the right way.
 
<a href=showthread.php?s=&postid=7966424#post7966424 target=_blank>Originally posted</a> by David Grigor
Instead of coming up with all this stuff, why don't you just address the root cause and either drill it or take it somewhere to get drilled.

30g tank is not the end of the world to temporarily house your livestock in a tub while you drill or take it to get drilled. We aren't talking some 500lb monster that have to get 5 guys to move the thing. Take your lumps and do it the right way.

I am with you!!:rollface:
 
<a href=showthread.php?s=&postid=7958831#post7958831 target=_blank>Originally posted</a> by BeanAnimal
FWIW you can not run a motor on a non sine wave "UPS" which is what I imagine your "small computer battery pack" is. The setup will either damage the pump or backup... or worse cause a fire.
Sorry but I disagree. Mine is running and has been for 6 months with no problems.:rolleyes:
 
<a href=showthread.php?s=&postid=7965770#post7965770 target=_blank>Originally posted</a> by Driftwood
My APC UPS does have a sine wave output, not simulated sine. I will have to do some testing with it on battery. I have a mag9.5, not on the UPS that is 19Watts. I read that starting wattage for a motor is 5-7 times the normal usage. 19x7 is only 133, shouldn't the APC be able to handle almost 1000 watts? If I am understanding this wrong, please correct me because I was thinking about a second 1500 to run that mag and keep my sump going in an outage.

Yes, you are understanding this wrong :) We can get into a LONG discussion about UPS technology, but in the end the point will be that you get what you pay for and an $125 desktop UPS does not have much under the hood. Motor startup current depends on the motor, the load, and of course the voltage. "shaded pole" motors come in a few flavors, the two primary varieties being "induction" and "synchronos". In addition to "induction motors" there are also "split phase" motors. These produce more torque (think washing machine motor). So we are talking in general terms here and a modified wave form affects each type a little differently.

In any case, as I mentioned, the problem is not really one of "currnet" or "startup current". The problem arises from the fact that the field around the motors core is what turns the motor by alternating which pole (set of coils) is postive with regards to 0V. This is of course 60 times a second. An induction motor lags behind slightly to begin with... by chopping the top off of the waveform, the motor behaves like it has a "flat spot" at each cycles peak. This in effect causes the motor to lose a significant amount of torque. In essence the motor sees a reduced voltage due to the "short peaks". Without going into a LOT of detail, the problem is that the output of the inverter is not designed to handle the "choppy" signature that it sees while running the motor.

Just out of curiosity I dug out a manual to a cheap simulated sine 'cyberpower' UPS unit like the one SA057 is probably using. It has a bunch of caution statements, including one about aquariums and condensation. There isn't anything on there about motors causing it to potentially catch fire. I'm not trying to argue, I just don't quite believe you yet. :) I know, I'm stubborn, but I tend to be quite skeptical of anything until I can confirm it in more then one place.
I have several cyberpower units laying around here. To prove the same point to a local reefer, I plugged a mag 9.5 into a cyberpower 1000AVR. The result was not a fire, but I did burn the outputs up on the cyberpower as well as the AVR circuit. Of course they don't say anything about "motors" why would they? They are computer UPS systems and sold as such. Furthermore they are complete garbage. The "AVR" in these units is pure BUCK/BOOST technology and pretty much worthless. You may also want to know that the 1000VA units can handle nowhere near that in real world operation! They are not bad for a single desktop PC and LCD monitor... you get what you pay for.


Both of the reef podcasts I listen to recommended to their listeners that they get a UPS and connect it to at least one of their pumps to keep water movement going in the event of an outage. They even said to go get a cheap desktop UPS if you couldn't afford a real one. If there is a real danger someone should let them know so they can edit those episodes and let their listeners know.

Thanks!

Yes I would say without hesitation that the PODSCASTS should be edited right away. That is simply BAD information. It is common knowledge that AC motors should not be hooked up to anything that does not produce a true sine wave. This is as common sense and proven as not using a rheostat to vary the speed of a shaded pole motor. Just because some websites or podcasts say something is "ok" does not mean that it is!

If you doubt me, try giving APC a call. When your done there you may want to look at LIEBERT.COM and learn about UPS technology (wealth of information for the curious).

Enjoy :)
 
<a href=showthread.php?s=&postid=7966120#post7966120 target=_blank>Originally posted</a> by quangtam7
The problem is that his stand may not have enough room for extra tank so it has to be outside, that is why I said SMALL EMPTY tank or bucket that enough to fill drained water. Why silly?
As I re read the post, he is worry about losing siphon in the U tube which could overflow the main tank (not the sump) if the pump is not shut down, so this does not apply to his case.
He may want to mount a float switch near top of the main tank or in the sump (1-2" bellow water level in reverse). Of course, this could cause the pump to cycle on/off but won't overflow the tank or the sump

What exactly are you talking about?

If he has a siphon overlow, he has a sump (or closed loop I suppose). THE WATER IS GOING SOMEPLACE!

Your suggestion is to drill a hole in the tank and add a catch can? I said that was silly. Why drill a hole for a catch can when you could instead use it as the overlflow and eliminate the u-tube problem? I surely hope you see the point here.
 
<a href=showthread.php?s=&postid=7966863#post7966863 target=_blank>Originally posted</a> by SA057
Sorry but I disagree. Mine is running and has been for 6 months with no problems.:rolleyes:

Disagree all you want :) What type of pump and what type of UPS. Kind of an empty statement without any facts.
 

Your suggestion is to drill a hole in the tank and add a catch can? I said that was silly. Why drill a hole for a catch can when you could instead use it as the overlflow and eliminate the u-tube problem? I surely hope you see the point here. [/B]

I guess you did not read my post, please read it again. First I thought he was worry about water from the tank will overflow the sump onto the the floor, that is why I suggested drill a hole near top of the sump not the tank, so water will drain to the secondary tank/bucket if the sump can not handle the drained volume.
His fear is if the siphon breaks and the pump continue to run, it will empty the sump and overflow the main tank. He is looking for a way to shut down the pump if this happens. Even with the switch, he problem is like you said in your first post.
 
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Here is the solution, find 2" acrylic tubing (5-6" in length), seal the bottom, mount a floatswitch inside the tube, put some small rock/marbles in it (to keep it submersed) and hang it inside the tank with the top edge of the tube just 1/4-1/2" above water level. When the siphone breaks, water in main tank raises and fill up the tube, which in turn shut down the pump, as water drains back to the sump, that tube is still filled with water so pump will remain down.
 
<a href=showthread.php?s=&postid=7969223#post7969223 target=_blank>Originally posted</a> by quangtam7
Here is the solution, find 2" acrylic tubing (5-6" in length), seal the bottom, mount a floatswitch inside the tube, put some small rock/marbles in it (to keep it submersed) and hang it inside the tank with the top edge of the tube just 1/4-1/2" above water level. When the siphone breaks, water in main tank raises and fill up the tube, which in turn shut down the pump, as water drains back to the sump, that tube is still filled with water so pump will remain down.

A workable idea. Use the cup to "latch" the pump off. This will work if you have space and don't mind looking at it. The problem is that this is the display tank. Most of us wanted to get a reef tank because it was pretty. Not because it had lots of tubes and equipment visible in it. A latching relay you can hide.
 
<a href=showthread.php?s=&postid=7965770#post7965770 target=_blank>Originally posted</a> by Driftwood
My APC UPS does have a sine wave output, not simulated sine. I will have to do some testing with it on battery. I have a mag9.5, not on the UPS that is 19Watts. I read that starting wattage for a motor is 5-7 times the normal usage. 19x7 is only 133, shouldn't the APC be able to handle almost 1000 watts? If I am understanding this wrong, please correct me because I was thinking about a second 1500 to run that mag and keep my sump going in an outage.

Just out of curiosity I dug out a manual to a cheap simulated sine 'cyberpower' UPS unit like the one SA057 is probably using. It has a bunch of caution statements, including one about aquariums and condensation. There isn't anything on there about motors causing it to potentially catch fire. I'm not trying to argue, I just don't quite believe you yet. :) I know, I'm stubborn, but I tend to be quite skeptical of anything until I can confirm it in more then one place.

Both of the reef podcasts I listen to recommended to their listeners that they get a UPS and connect it to at least one of their pumps to keep water movement going in the event of an outage. They even said to go get a cheap desktop UPS if you couldn't afford a real one. If there is a real danger someone should let them know so they can edit those episodes and let their listeners know.

Thanks!

MAG 9.5 runs at 93 watts not 19. :)
 
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