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Togle switch amps
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Ralph Mowery
Feb 16, 2019, 6:29:11 PM2/16/19
to
Why are switches being rated at different amps ?
I see lots of them on ebay rated for 10 maps at 240 volts and 20 amps at
120 volts.
Looks to me they should have the same amp rating at all voltages. The
do not specify any kind of load like something that would draw a larger
current at startup with a higher voltage.
Fox's Mercantile
Feb 16, 2019, 6:30:57 PM2/16/19
to
--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com
Phil Hobbs
Feb 16, 2019, 6:34:00 PM2/16/19
to
fuses rated at 250VAC are also rated at 32VDC.
A friend of a friend was severely injured a couple of weeks ago by an
arc flash at a 480V breaker panel. Turning off high-energy circuits is
no joke.
Cheers
Phil Hobbs
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510
http://electrooptical.net
http://hobbs-eo.com
Phil Allison
Feb 16, 2019, 7:38:20 PM2/16/19
to
Ralph Mowery wrote:
>
>
> Why are switches being rated at different amps ?
>
> I see lots of them on ebay rated for 10 maps at 240 volts and 20 amps at
> 120 volts.
>
** The same switch is likely rated at 20 maps for DC switching up to 24V. Above that voltage, contact to contact arcing will become very severe or continuous.
>
>
> Why are switches being rated at different amps ?
>
> I see lots of them on ebay rated for 10 maps at 240 volts and 20 amps at
> 120 volts.
>
> Looks to me they should have the same amp rating at all voltages.
Inrush surge capacity is another matter, requiring both heavier contacts plus a strong switch off force to pull contacts apart that have become slightly welded.
.... Phil
.... Phil
Ralph Mowery
Feb 16, 2019, 7:53:33 PM2/16/19
to
In article <5badnWXL29d8APXB...@supernews.com>,
pcdhSpamM...@electrooptical.net says...
turned on a breaker that was only a 20 amp rating for a small motor.
Not sure what hapened, but it melted down a whole bank of about 30 or 40
cubicals in a load control center. That bank ws fed with around 400
amps from a larger breaker in what we called a substation room. It
meleted out the bus bars on that load control center.
When working I dealt with 480 V 3 phase equipment almost daily. Lots of
10 to 100 hp motors and some heaters that were fused at 250 amps.
pcdhSpamM...@electrooptical.net says...
>
> A friend of a friend was severely injured a couple of weeks ago by an
> arc flash at a 480V breaker panel. Turning off high-energy circuits is
> no joke.
>
>
>
I have seen the results of a 480 volt 3 phase 'blow up', Fellow at work
> A friend of a friend was severely injured a couple of weeks ago by an
> arc flash at a 480V breaker panel. Turning off high-energy circuits is
> no joke.
>
>
>
turned on a breaker that was only a 20 amp rating for a small motor.
Not sure what hapened, but it melted down a whole bank of about 30 or 40
cubicals in a load control center. That bank ws fed with around 400
amps from a larger breaker in what we called a substation room. It
meleted out the bus bars on that load control center.
When working I dealt with 480 V 3 phase equipment almost daily. Lots of
10 to 100 hp motors and some heaters that were fused at 250 amps.
Phil Hobbs
Feb 16, 2019, 7:57:53 PM2/16/19
to
stuff. The FOAF was burned over more than 50% of his body. :(
tabb...@gmail.com
Feb 18, 2019, 5:32:06 AM2/18/19
to
NT
Boris Mohar
Feb 19, 2019, 5:27:38 AM2/19/19
to
On Sat, 16 Feb 2019 19:57:46 -0500, Phil Hobbs
<pcdhSpamM...@electrooptical.net> wrote:
>On 2/16/19 7:53 PM, Ralph Mowery wrote:
>> In article <5badnWXL29d8APXB...@supernews.com>,
>> pcdhSpamM...@electrooptical.net says...
>>>
>>> A friend of a friend was severely injured a couple of weeks ago by an
>>> arc flash at a 480V breaker panel. Turning off high-energy circuits is
>>> no joke.
>>>
>>>
>>>
>>
>> I have seen the results of a 480 volt 3 phase 'blow up', Fellow at work
>> turned on a breaker that was only a 20 amp rating for a small motor.
>> Not sure what hapened, but it melted down a whole bank of about 30 or 40
>> cubicals in a load control center. That bank ws fed with around 400
>> amps from a larger breaker in what we called a substation room. It
>> meleted out the bus bars on that load control center.
>>
>>
>> When working I dealt with 480 V 3 phase equipment almost daily. Lots of
>> 10 to 100 hp motors and some heaters that were fused at 250 amps.
>>
>>
>>
>>
>>
>It's good to wear the Nomex suit and helmet when hacking with that
>stuff. The FOAF was burned over more than 50% of his body. :(
>
>Cheers
>
>Phil Hobbs
They say that those make good body bags.
<pcdhSpamM...@electrooptical.net> wrote:
>On 2/16/19 7:53 PM, Ralph Mowery wrote:
>> In article <5badnWXL29d8APXB...@supernews.com>,
>> pcdhSpamM...@electrooptical.net says...
>>>
>>> A friend of a friend was severely injured a couple of weeks ago by an
>>> arc flash at a 480V breaker panel. Turning off high-energy circuits is
>>> no joke.
>>>
>>>
>>>
>>
>> I have seen the results of a 480 volt 3 phase 'blow up', Fellow at work
>> turned on a breaker that was only a 20 amp rating for a small motor.
>> Not sure what hapened, but it melted down a whole bank of about 30 or 40
>> cubicals in a load control center. That bank ws fed with around 400
>> amps from a larger breaker in what we called a substation room. It
>> meleted out the bus bars on that load control center.
>>
>>
>> When working I dealt with 480 V 3 phase equipment almost daily. Lots of
>> 10 to 100 hp motors and some heaters that were fused at 250 amps.
>>
>>
>>
>>
>>
>It's good to wear the Nomex suit and helmet when hacking with that
>stuff. The FOAF was burned over more than 50% of his body. :(
>
>Cheers
>
>Phil Hobbs
--
Boris
---
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