Generator question: Is flickering power bad for a fridge?
My neighbor bought one of these generators and when he uses it, the lights in his house flicker because the electricity isn't "regulated". My question is whether this could damage your refrigerator because the fridge has a compressor and everything in a compressor is under pressure. I read that you can't turn some air conditioners off and then on again without waiting three minutes because you could damage them. Can it damage a fridge?
http://www.harborfreight.com/engines-generators/gas-engine-generators/800-rated-watts-900-max-watts-portable-generator-66619.html
What do you think?
http://www.harborfreight.com/engines-generators/gas-engine-generators/800-rated-watts-900-max-watts-portable-generator-66619.html
What do you think?
Comments
Can someone draw me a simple diagram on how to hook it up. A neighbor has an extention type cord wired into his electric and he has a way of switching the power. An electrician has seen it but I don't know if the same electrician approved it. I may want one of these generators to run a sump pump or power my fridge as we just went through Hurricane Irene.
Does Mouser or Digikey carry a capacitor that is suitable?
Although I have read a ton about people who have had problems with their electronic things and generators. And newer refrigerators have electronics in them! So that could be a problem.
Recently they have come out with "electronics friendly" generators. Search google.com for the words (including quotes)...
"electronics friendly" generator
Another solution is an "online" "true sine" UPS. These create their own "perfect" electricity 100% of the time. Other UPS only create electricity when running on the batteries, but pass through the mains electricity when not on battery. The word "online" means 100% of the time. So search google.com for the words (including quotes and +)...
+online +"true sine" +UPS
I've not had luck searching for "power line conditioners". There is a lot of "sales hype" with some of these which are just power strips. And the larger power line conditioners cost a small fortune or will be for 3 phase industrial use.
Look at the wattage on the generator. And convert amps to watts for appliances with the following calculator. Use Single Phase...
http://www.jobsite-generators.com/power_calculators.html
The dangerous failure mode for a fridge is when the mains supply goes too low for a long time - the motor stalls and then overheats, potentially then bursting and catching fire. Since it is immersed in an oil bath so it is an effective incendiary device (note that the refrigerant under pressure is not the issue). However power generating companies are well aware of the dangers of such brown-outs and the network should automatically trip out if this happens. With your own generator this is your own responsibility (a good generator control circuit will do the right thing and protect against under and over-voltage.)
I suspect modern efficient fridges have much less powerful motors than in the past and are less likely to be able to overheat to the point of failure. Googling suggests fridge-related fires are rare.
I would NOT connect these (and any other ones) capacitors across 120V AC unless you're up for a big KABOOM. Make sure that you're far away when you turn on the AC. You may film that too. It may actually be a hit on youtube.
Seriously though... These AC caps are used as the AC motor starters and/or run capacitors. NEVER connect them directly to the AC hoping to smooth out the voltage level like for DC.
I am so glad you posted that and I second that advice.
I will stay safe and agree with both of your advice.
Good to hear. Wouldn't want to loose any forum members.
Nonetheless, refrigerators are rather old technology that generally accommodates brown outs and voltage spikes better than solid-state devices.
As a kid, I learned the hard way that a capacitor inserted wrongly into an A/C line is equal to a short circuit. I blew up an AC outlet and the capacitor in my Elementary Electronics course and the teacher was livid. If the same capacitor was used on a DC circuit, it might reduce the flicker - but one MUST get very clear about the differences of AC and DC when using coils and capacitors.
There are different guage wires in extention cords. The old long orange ones are good enough to run an electric lawnmower on. I've run an electric snowblower on them and haven't noticed a difference between that and 13 or 15 guage extention cords.
If you must use an extension cord because you want to keep the generator outside (to prevent carbon monoxide poisoning and noise), it is far better to set up a separate limited power distribution than to try to drive the whole home. Somebody that doesn't understand electrical distribution is likely to turn more things on. Alternatively, shut down unneeded circuits at the circuit breaker box if you must use the house wiring to distribute power AND consider using some ROMEX (with nice solid copper 12 gage wire) to connect the generator to the house service.
The old extention cords made in Mexico were sufficient. Now Lowes sells extention cords made from China and I can tell the difference so I buy them from Home Depot which gets their cords made from the Phillipines which is a little heavier.
I have a bunch of broken extention cords that I have to fix because I cut them accidentally with the hedge shears.
But we're talking about the power going out for 2 1/2 hours to five hours and having to run a sump pump for a time if the neighbor's basement gets filled by a creek. It is running a device to help maintain the temperature. My mother in law's power went out for 11 hours and she still had ice cubes because she doesn't open the fridge. We're talking about running it a little to maintain the temperature or having a light but nothing long term.
I must admit I sometimes despair at how quickly bad and dangerous advice slides into discussions. Thankfully not often here.
The little gen set the OP linked to is a fine product and will run the referred to refrigerator for years without causing any damage. The "flickering" is just the little generator momentarily bogging down as the compressor cycles. Ironically, the cheaper gen sets handle heavy starting loads (proportional to their capacity) better because their less technically advanced voltage regulators allow the voltage to sag to give the same effect as a reduced-voltage starter.
The suggestion of the capacitor as a solution just boggles the mind in its glaring lack of understanding. Luckily, it was noted and I think the message received. And, suggesting a household refrigerator compressor would blow up in an oil-fueled firebomb under low voltage is a good topic for a sci-fi story but bears no relationship to any normal fridge compressor with built-in thermal overload and fed by a circuit breaker/fused circuit.
As has recently been discussed in other parts of the forum, sometimes conjecture and ad-libbed urban legend does not add to the Op's search for answers.
/mini rant OFF
We have a new Samsung fridge which no doubt contains more electronics than my office desk.
I may need to run this on an old Kawasaki non inverter type generator. It works fine with the washing machine which has an electronic power board but It will not work a desktop PC run through a UPS power box.
What do you think the risk is of running the new fridge on the old gen set?
Regards,
Tropicman
@Stamptrol Yes and no for all the wrong reasons .!
AC EE101 . Power factor correction .
Gen sets Like a PF of 1 ...... Esp the inverter ones !!!!!!!!!!!!!
So adding a cap for PFC is not a bad idea IF the end user does some AC math .
that said the idea of a HUGE cap on the line is bad bad bad . and using a polarized cap is just a nasty .
most of those non oil caps are not rated to run continuously with AC on them .
they are Starting caps ......... Oil filled ones are known as running caps ( used to make a phase shift in a AC single phase motor) and are AC rated .
the latter If with math may be OK as PFC caps !!!!!!!
many new CFLs and PC PSUs are PFCed ..
However you again need to do Trig to get the right cap..
Simply put . you shove a 2000 uf cap accros a AC Line . its gonna look like close to a short .
how would a normal UPS help ?
Bill has it right .
unless its a $1000 Line Interactive or ONLINE UPS .
a normal UPS is not gonna do any good .......
Okay soo Again with out knowing the max and min on the power supplys that run the fancy parts of the fridge . I have no way to put a risk assement on it . However ....
If the PSU that runs the fancy stuff can take 170V or more then I would not worry .provided your genset is is goood order ....... I need more data Really .......
you really need to \ weagh the price of a new fridge VS the food in it VS the reason your lacking mains power ......
Anyway, the point of bringing this up here is that, if you suffer from fluctuating or fading voltage, it might be advantageous to add a start booster to the compressor to make sure it starts under adverse conditions. I don't recall the one that I purchased being very expensive, and it's kept my old workhorse alive all these many years later.
-Phil
'Splain por favor?
-Phil
Depends on the length and the load, and what the device is built for. The better ones incorporate the thinner wires and a suitable length into the design.
Personally, for anything over about 20-30 feet, I run 10 gauge cords. They aren't cheap, but I've never, ever had anything fail or run poorly up to 100' (two 50' in series.) Most often, I'll just lead out with the 10, and then use an ordinary one from there.
A similar thing goes for house wiring. I've noted a trend in newer homes to settle on 14 gauge wire almost everywhere. For a larger home, and a few junctions in the circuit, there is a considerable drop! I'll see them do it on 15A circuits too, which blow early due to that drop, and it's not approprate if a 15A socket needs to be dropped in somewhere.
The last one I did saw 10 gauge from the breaker to the room junction, unless it's a short distance, then I used 12. From that junction to the outlets, I used 12, and then 14 to connect a few short distance, parallel wired outlets. Honestly, the difference in wire cost wasn't all that much, given some planning. The nice thing about doing it that way, is you generally exceed local code requirements, and if a 15A socket is needed somewhere, you've got it covered.
Lights a bit brighter, portable heaters not blowing breakers, etc... And nice, cool, long lasting circuits. Nobody wants to tear into that stuff. And on the off chance somebody pushes it someday, the wires are there to handle it. The home I'm in right now was done with 12 & 14, and it's kind of crappy. One of these days...
Again, for nicer tools and appliances, they've designed it well, basically reducing the need or benefit from the larger diameter wires and cords. These days, I'm seeing way too many cheap-o things that do not perform well, or generate excessive heat at more than average room length distances on smaller diameter wire. After I lost a drill assembling a fence, that was it for me.
I would worry about any real length on those smaller diameter wires when using a generator. Maybe it's just me, but I like to run the bigger stuff. Buy it once, and you've got it, unless something bad happens.
@Phil: Never heard of such a thing! I have two units with the sealed compressors and they are getting older. So far, they've performed fine, and that may be due to my preferences on wiring to them above, but I'm filing this info away for when I will need it someday. Seems like a great "life extension" option for older, but perfectly servicable appliances. I have an older "coffin" style freezer that gets right down to about 10 degrees F. Love that thing. Quiet, and old. Would hate to replace it and it's been in service for a very long time.
Another problem is that people think nothing of setting the generator far and away to minimize noise and carbon monoxide, and then run 100 feet of rather flimsy extension cord to what they expect to power. A refigerator is a rather demanding load.... needs a better than average extension cord.
...THAT I can understand!
-Phil
I used to sell / service appliances for many years. Here's an example of what you most likely used. I've used many of these over the years-
http://www.amazon.com/Supco-RCO810-Capacitor-Overload-Device/dp/B004XS1P5E
They are sized by the HP of the compressor. Supco is a large supplier in the aftermarket parts for appliances. Just google Supco 3-n-1.