I need to charge a set of batteries right now, but the manual says to plug the charger straight into the wall outlet. I'm afraid to do so, cause it's storming right now and i'm worried if i plug it straight into the wall, if their is a power surge, it may fry the charger. why can't i plug it into a surge protector?
Why does battery chargers say not to plug into extension cords or power strips?
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Mr Happy
Flashlight Enthusiast
You can. There is no reason at all why not.
I'll hazard a guess it's because the manufacturer does not want to be held responsible when someone's house burns down because it was actually a faulty extension cord that caused it. It is obviously a bigger concern plugging high draw things into low draw extensions but in this day and age...
I was more concerned about surge protectors, (perhaps i should have made the question more clearer) I'd like to plug my chargers into my APC UPS so that way it would be protected from brown noise, power spikes, surges, etc. when the power gets to high or to low, it will kick off of the main AC and run on the battery until the level comes back down to normal, then it goes back to the main AC lines. i don't want to cause a fire, yet i also don't want to damage my equipment. last night the power surged in my area and the transformer overloaded and shut down, and i had the charger plugged into the main line, and i was worried it would fry the batteries or the charger. i'd like to plug it into the UPS (it has 6 plug in's, 3 are to the battery and surge protector, and 3 are NOT to the battery, just the protector)
Being hooked up to a surge protector, would the batteries still be able to fully charge, or would it cut down on the charging current the charger is putting out, meaning longer charge time and/or not being able to fully charge the batteries?
Being hooked up to a surge protector, would the batteries still be able to fully charge, or would it cut down on the charging current the charger is putting out, meaning longer charge time and/or not being able to fully charge the batteries?
StorminMatt
Flashlight Enthusiast
I wouldn't worry about this. A heater would be a different matter. But a battery charger draws less current than the average table lamp.
moldyoldy
Flashlight Enthusiast
The consumer grade APC UPS units operate as a pass-thru for the AC line on the battery supported side. If the power fails, the circuitry starts the inverter in a few milliseconds and continues supporting the load. During an AC power failure, the UPS outlets that are only "surge protected", and not with battery support, drop out and shut off. IOW, plugging in the battery charger to either side of the UPS is OK. It just depends if you want charging of your batteries to continue during a power failure.
Power Me Up
Enlightened
I run all of my office off of an APC Smart UPS, including several chargers - no problems here!
With a UPS that puts out a normal sine wave, the device has no way of knowing that it's running off a UPS and will work exactly as normal. If you've got a lower end UPS that puts out a modified sine wave (i.e. basically a stepped square wave) then some devices don't work so well, but most power bricks these days are switch mode types and will still run fine.
moldyoldy
Flashlight Enthusiast
additional comment: UPS units generally have only surge protection via a variety of devices which include "Full time multi-pole noise filtering", but no dB specification is commonly given. However the APC SurgeArrest units add an important feature - EMI/RFI Noise rejection (100 kHz to 10 MHz). This can vary from 20dB to 70dB. FWIW, a Topaz true isolation transformer has a rejection of 120dB. IOW, 70dB for an 3 stage RLC filtering system is impressive. This keeps a lot of line noise out of the systems. Most battery chargers will not be affected by noise reduction, only AC voltage spike reduction. However radios and such will care about incoming noise reduction. For an example, look at the APC Network SurgeArrest device with 70 dB of noise reduction.
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Moldyoldy & others are correct, a UPS will protect the device.Many UPS & investors are square wave which works fine for most devices except some laser printers.You need a surge protector on the ups.FYI re spikes, surges etc. these take out modems and other light electronic items.Electrical companis pay vastly more due to "brown-outs" or low voltage.These kill induction motors on freezes, refrigerators, washer & dryers, HVAC compressor etc.Your ?They do that for liability purposes.My information was gathered from 30+ decades in electrical generation.Hope this helps.I need to post regarding ways to cut electrical bills, when I get the desktop back online.
But, like a CFL or other non-linear loads, a charger without power factor correction can end up pulling some seriously high peak current compared to the RMS current.
Probably still not enough to cause real problems with a good sized extension cord or power strip, but one more nail in the coffin of legal liability if they do not warn against it.
With a power strip you could connect 8 chargers to one wall outlet, all drawing a high peak current.
Remember that when looking at heating in an external series resistance (the cord and house wiring), the power dissipated in that resistance by a non-linear load can increase faster than the total power going to the load, as the duty cycle decreases but the power drain remains the same.
The additional reason that some appliances, including toasters, coffee pots, etc. warn against using an extension cord is that they are worried that if you put it too far from the outlet or let the cord dangle off a counter, it is more likely to be tripped over, potentially causing an unsafe condition. Again, more aimed at heating appliances than chargers, but putting that language in becomes a habit.
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uk_caver
Flashlight Enthusiast
To be fair, the decades before Faraday weren't very busy.
Verndog
Enlightened
HOW old are you??!
Sent using Tapatalk 2.
It would appear well over 300 yrs. old. Possibly he is confusing power trips with power strips. :devil:
The reason Sanyo NiMH chargers say to always plug directly into a wall outlet is based on the fact that they have temperature monitoring to aid in determining state of charge. What they are really driving at is that the operation is predicated on the charger being in the upright position with the sliding door closed. This is hard to achieve at the end of an extension cord, or the horizontal outlets frequently found on a UPS.
OP: so it depends on what charger(s) you are talking about. Can you be more specific?
OP: so it depends on what charger(s) you are talking about. Can you be more specific?
Mr Happy
Flashlight Enthusiast
The instructions for that charger simply say "Never plug battery chargers into an extension cord."
There are many possible reasons for this advice. One possible reason is that this charger uses a "wall wart" power supply. Such supplies have been known to melt and possibly catch fire if they fail. If the wall wart is plugged into the wall, a meltdown is safer than if it is sitting on the end of an extension cable where it might be next to something flammable like drapes or paper.
Another possible reason is that the charger needs to run for a long time unattended, and someone may unplug the extension cord thinking it is not in use.
You have to pick your own reason why you shouldn't plug your charger into an extension cord. Your reason might be different from other people's reasons. If you can't think of any reason to obey that instruction then you may safely ignore it.
Given the manual for that unit http://www.energizer.com/SiteCollectionDocuments/pdf/rechargeable/CHFC2_Instructions.pdf, without any hesitation whatsoever my evaluation is that the instruction not to plug it into an extension code is utterly baseless BS. Clearly the orientation of the unit is not dependent at all on how or where the wall wart is plugged in.
uk_caver
Flashlight Enthusiast
I've certainly seen it happen that [at least part of] a manual seems to have been written by copying and editing a manual for a different previous piece of equipment.
Lists of 'safety' or 'correct use' type instructions might be the kind of thing where that would be expected to happen most often, since so much will be the same for multiple products ('don't use in the rain', 'don't use in the bath', etc)
Lists of 'safety' or 'correct use' type instructions might be the kind of thing where that would be expected to happen most often, since so much will be the same for multiple products ('don't use in the rain', 'don't use in the bath', etc)
Mr Happy
Flashlight Enthusiast
I can certainly imagine it is advised to plug a "wall wart" directly into a wall socket for reasons of air circulation, cooling, and clearance from other objects. I don't think battery chargers are the only items where I have read this advice.
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