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Re: [TCML] Power Factor Correction



    
Reseting circuit breakers and replacing fuses without any.  then I added 1 at a time till 9 which worked best but I added one more because of ocd.  


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-------- Original message --------
From: Ed <evp@xxxxxxxxxxx> 
Date: 12/04/2016  21:29  (GMT-06:00) 
To: Tesla Coil Mailing List <tesla@xxxxxxxxxx> 
Subject: Re: [TCML] Power Factor Correction 

What happens when you don't use any?  That capacitance has a reactance 
of around 6 ohms but depending on the instantaneous line voltage phase 
when you close the switch you might get a very high capacitor charging 
current.  Won't happen with an NST alone, with or without capacitor on 
secondary.

Ed


On 12/4/2016 5:00 PM, wt5y wrote:
>      
> Same here when I parallel 3 12kv 60's sometimes blows fuses in variac.  I use 10 50uf ac caps.
>
>
> Sent from my Samsung GALAXY S5™, a Cricket 4G LTE smartphone
>
> -------- Original message --------
> From: Gary Lau <glau1024@xxxxxxxxx>
> Date: 12/04/2016  17:54  (GMT-06:00)
> To: Tesla Coil Mailing List <tesla@xxxxxxxxxx>
> Subject: Re: [TCML] Power Factor Correction
>
> Indeed, my 15/60 NST  pulls over 20 Amps from the wall WITH PFC caps.
> Having the PFC caps is the difference between tripping and not tripping the
> breaker.  And while I've never attempted to measure it, I believe that the
> line voltage applied to the NST primary is greater with the caps by virtue
> of lower IR losses in the mains wiring.  More volts is more power to the
> sparks!
>
> Regards, Gary Lau
> MA, USA
>
> On Sat, Dec 3, 2016 at 11:59 PM, jimlux <jimlux@xxxxxxxxxxxxx> wrote:
>
>> On 12/3/16 7:33 PM, Chris Boden wrote:
>>
>>> I understand that, but....with an NST powered coil, it's rather moot isn't
>>> it?
>>>
>> You're drawing more current through your variac, which will get hotter.
>> And while a single 30mA 15 kV NST is only going to be 400-500 VA, if you
>> start ganging them up in parallel, or getting a 60mA 15 kV unit, then
>> you're getting up towards where the current draw is an issue
>>
>>
>>
>>
>>> I mean, you're drawing only a few hundred watts. The "wasted power" isn't
>>> enough to trip the breaker, and the impact in your electric bill is on par
>>> with your doorbell.
>>>
>> The bill will be the same whether you have PFC or not - your meter only
>> measures active power, not reactive power.  So if you were drawing, say, 15
>> A @ 120V (1800VA) and the PF were 50%, your meter is only going to spin for
>> a 900W load.
>>
>> (there's a very small effect from the IR losses in the wiring because of
>> the reactive power, but it's "small".. IR loss is <2% with 100% PF, and
>> only slightly more (<4%) with 50% PF
>>
>>
>>
>>
>>> Maybe I'm missing something, my electric bills are a little different than
>>> most. It just seems like a lot of effort for very little tangible gains.
>>>
>>> We certainly don't worry about it here in the lab.
>>>
>> I sort of agree - there's not a lot to be gained by worrying about PF.
>>
>>
>>
>>
>>
>>
>>
>>> On Sat, Dec 3, 2016 at 7:58 PM, jimlux <jimlux@xxxxxxxxxxxxx> wrote:
>>>
>>> On 12/3/16 4:03 PM, Chris Boden wrote:
>>>> The question I have is......Why? Why would you want to lower the PF?
>>>>>
>>>>>
>>>>> Total line current is less - the meter spins slowly for the current, but
>>>> the breaker will trip.
>>>>
>>>> if you have 71% PF, you'll draw 14 amps from the socket, but only be
>>>> really using 10 of it to make sparks.
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> _______________________________________________
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>>>>
>>>>
>>>
>>>
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