Author Topic: Circulating Pump  (Read 4694 times)

Offline busnut104

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Circulating Pump
« on: July 04, 2006, 08:00:08 PM »
I have a std. 110 circulating pump which run my heating system, It works perfect on the shore line but when I try it on my 3000 watt inverter the inverter is making funny noises and I don't leave it on long enough to see if the pump is running, Iam afraid that I will fry my inverter, Iam not sure at this time what the draw is on the pump, but it is small and I can believe the inverter is not large enough, any Ideas. Thanks. I was just thinking, I just installed a digital unit that turns on the pump when hot water is called for maybe since I have a modified sine wave, this is unable to run the digital unit.??????
« Last Edit: July 04, 2006, 08:20:02 PM by busnut104 »

Offline JackConrad

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Re: Circulating Pump
« Reply #1 on: July 05, 2006, 05:14:57 AM »
Can you bypass the digital controller and see if the pump runs?  We have a problem with a digital clock radio in our bus when operating on the modified sine wave inverter, but it does not make then inverter make strange noises, the only thing that happens is that the clock runs fast (I think the clock is counting each step in the modified sine wave). Can you connect the pump to "regular" 110 volt and get an amp reading on the pump?  Jack
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Offline DrivingMissLazy

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Re: Circulating Pump
« Reply #2 on: July 05, 2006, 05:36:11 AM »
The clock on my microwave and bedroom clock would not run properly on a modified square wave inverter either. The inverter was in a lower compartment so i could not hear it. Of course, the clocks put very little drain on the inverter. The microwave would operate properly though.
Richard



Can you bypass the digital controller and see if the pump runs?  We have a problem with a digital clock radio in our bus when operating on the modified sine wave inverter, but it does not make then inverter make strange noises, the only thing that happens is that the clock runs fast (I think the clock is counting each step in the modified sine wave). Can you connect the pump to "regular" 110 volt and get an amp reading on the pump?  Jack
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Offline boogiethecat

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Re: Circulating Pump
« Reply #3 on: July 05, 2006, 06:58:44 AM »
You guys are finding out why modified sine inverters are cheap.  There's a LOT of things they won't properly power up, and they cause a lot of trouble.
"Modified sine" is mostly salesmanship BS that in english says "square wave inverter with meager attempt at filtering the crap out of their output". 
The deal is that many things, like motors, need a pure sine wave to run, because they operate almost solely on the 60 hz fundamental frequency, the sine wave.
A modified sine inverter contains tons of harmonics (energy at higher frequencies than 60hz) in addition to the sine wave, and all of the energy in those harmonics (and it's a lot) show up in things such as motors, as heat.  So motors get much hotter than they should, if they decide to operate at all, which many won't.   I'd rather have nothing than a modified sine inverter.  They're good for running lightbulbs and electric drill motors, but in my opinion not much more.  And the interference they generate screws up a lot of electronic things, especially computer and wireless related...
Spend the bucks, get a true sine, and get over your troubles!! :)
« Last Edit: July 05, 2006, 07:03:17 AM by boogiethecat »
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Offline DrivingMissLazy

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Re: Circulating Pump
« Reply #4 on: July 05, 2006, 07:56:01 AM »
I have to disagree with you to a certain extent. Although my clocks did not run properly, I could live with that. I really did not need the digital clock on the Microwave.

 I used a MSW inverter many years and was  generally happy with it. I did not try and run an A/C as the inverter was not large enough. Everything else that I needed AC power for such as TV's, lights, laptop computer, Direct TV converter, the microwave and other small AC appliances all worked OK.

Based on that, I see no reason why anyone should spend the extra money if they are not trying to run their air conditioners.

If the inverter is large enough, I really do not believe that any extra heat, generated by the modified sine wave, would really hurt an A/C motor. Motors have an extremely  large built in tolerance for heat.  I have never heard of an A/C  motor being damaged by operating off a MSW inverter. That is not to say that it has not happened. LOL
Richard



You guys are finding out why modified sine inverters are cheap.  There's a LOT of things they won't properly power up, and they cause a lot of trouble.
"Modified sine" is mostly salesmanship BS that in english says "square wave inverter with meager attempt at filtering the crap out of their output". 
The deal is that many things, like motors, need a pure sine wave to run, because they operate almost solely on the 60 hz fundamental frequency, the sine wave.
A modified sine inverter contains tons of harmonics (energy at higher frequencies than 60hz) in addition to the sine wave, and all of the energy in those harmonics (and it's a lot) show up in things such as motors, as heat.  So motors get much hotter than they should, if they decide to operate at all, which many won't.   I'd rather have nothing than a modified sine inverter.  They're good for running lightbulbs and electric drill motors, but in my opinion not much more.  And the interference they generate screws up a lot of electronic things, especially computer and wireless related...
Spend the bucks, get a true sine, and get over your troubles!! :)
« Last Edit: July 05, 2006, 07:59:40 AM by DrivingMissLazy »
Life should NOT be a journey to the grave with the intention of arriving safely in an attractive and well preserved body. But rather to skid in sideways, chocolate in one hand, a good Reisling in the other, body thoroughly used up, totally worn out and screaming:  WOO HOO, what a ride

Dallas

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Re: Circulating Pump
« Reply #5 on: July 05, 2006, 08:25:10 AM »
You guys are finding out why modified sine inverters are cheap.  There's a LOT of things they won't properly power up, and they cause a lot of trouble.
"Modified sine" is mostly salesmanship BS that in english says "square wave inverter with meager attempt at filtering the crap out of their output". 
The deal is that many things, like motors, need a pure sine wave to run, because they operate almost solely on the 60 hz fundamental frequency, the sine wave.
A modified sine inverter contains tons of harmonics (energy at higher frequencies than 60hz) in addition to the sine wave, and all of the energy in those harmonics (and it's a lot) show up in things such as motors, as heat.  So motors get much hotter than they should, if they decide to operate at all, which many won't.   I'd rather have nothing than a modified sine inverter.  They're good for running lightbulbs and electric drill motors, but in my opinion not much more.  And the interference they generate screws up a lot of electronic things, especially computer and wireless related...
Spend the bucks, get a true sine, and get over your troubles!! :)

Gary,
I have a MSW 2.5KW inverter that runs my fridge, lghts, TV, Stereo and computers when I'm not on pole power. One computer I'm using is a HP 400Mhz that has been running mostly nonstop for the last 8 years. most of that time on the inverter. The fridge, albeit, not an airconditioner, seems to run cooler on the inverter than the pole. This is only through observation with the IR temp gun pointed at the compressor motor. It isn't through scientific observation. I've run one of my small a/c's from the inverter and had no problem, but I wouldn't try to run both of them as I'm sure the inverter would be overloaded if all the loads started at close to the same time.

Sure, I'd like to have a true sine wave inverter, if nothing else, for the efficiency they offer. Unfortunately, my budget, my wife and the need to buy groceries precludes my ability to be able to afford one.

I HAVE seen really cheap MSW inverters that really suck at starting heavy loads, and actually watched as a friend of mine installed a Coleman inverter (1750W) that was meant to only run a TV, Stereo and Satelite system. Even though it was hooked up correctly, it fried every piece of equipment it was hooked to.

In conclusion, I think that like with most other tools, there are some great ones, some not so great ones, some that work and some that really shouldn't be on the market at all. Making a blanket statement that they are all bad if they are modified sinewave is inherently misleading.

Dallas

Ncbob

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Re: Circulating Pump
« Reply #6 on: July 05, 2006, 01:56:30 PM »
Dallas, while you're doing wonders with your antique computer...you need to get into the 21st Century.  ;)

Mayhaps we could collectively bring some of our old computers to Timmonsville in October and build you something worth your mettle?

Egads man!  400Mhz went out with high button shoes! :D

Bob

Dallas

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Re: Circulating Pump
« Reply #7 on: July 05, 2006, 02:23:53 PM »
Dallas, while you're doing wonders with your antique computer...you need to get into the 21st Century.  ;)

Mayhaps we could collectively bring some of our old computers to Timmonsville in October and build you something worth your mettle?

Egads man!  400Mhz went out with high button shoes! :D

Bob

But, none the less, it travels the information super highway as fast as the new super duper 17 bazillion mhz models. At least when using dial up!
Plus I have boxes and boxes of parts to build another, I just haven't found a need to replace that particular machine.

Dallas

Ncbob

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Re: Circulating Pump
« Reply #8 on: July 05, 2006, 04:47:06 PM »
Then....there was the tortiose and the hare......  Slow and easy usually wins the race. ;)

Bob