I'm not sure what resistor you are referring to Rich.
In the power supply that bit me there were two 100K 225W resistors in series
across 4KV and one was open - no arcing. Examination of the open resistor
showed only a hairline crack a couple inches from one end.
If you mean the current limiter you propose in a shorting stick, would you
trust it to arc so you knew it was open?
I'll go for the big bang of a heavy hunk of wire right to ground. Safety
glasses on, one hand in my pocket.
Someone mentioned watching the HV meter. In the case I had, the HV meter
indicated zero - that's the bug I thought I had. The metering was done
across a small (10K ?) 25W resistor which was at the bottom of the open
bleeder. Never trust the meter!
73, Bill N2BC
----- Original Message -----
From: "R. Measures" <r@somis.org>
To: "Bill Coleman N2BC" <n2bc@stny.rr.com>
Cc: "AMPS" <amps@contesting.com>
Sent: Sunday, April 24, 2005 8:40 PM
Subject: Re: [Amps] Shorting Sticks
On Apr 24, 2005, at 2:26 PM, Bill Coleman N2BC wrote:
> It won't get warm at all if it's open...
What will prevent the open from arcing?
>
>
> ----- Original Message ----- From: "R; Measures" <r@somis.org>
> To: "Bill Coleman N2BC" <n2bc@stny.rr.com>
> Sent: Sunday, April 24, 2005 5:18 PM
> Subject: Re: [Amps] Shorting Sticks
>
>
> A typical value for a current limiter resistor in a shorting stick is
> 400 - 1000-ohms, 100w. Discharging even 200J barely gets a 100w
> resistor warm.
>
> On Apr 24, 2005, at 1:52 PM, Bill Coleman N2BC wrote:
>
>> As one that has literally come across an open 225W bleeder.... I would
>> never
>> trust a resistor in series with the shorting stick. If the caps are
>> charged, something has already failed. If the caps get damaged, too
>> bad. I
>> would rather kill a few bucks worth of parts than me.
>>
>> 73, Bill N2BC
>>
>> PS: It's a good idea to routinely test the shorting stick too.
>
> Agreed, but if the I-limiter resistor is open, there would be a
> considerable fireworks show.
>>
snip
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