Nice - they are pretty fashionable, too.  Win/win.

On Fri, Apr 1, 2016 at 3:37 PM, Ken Hohhof <[email protected]> wrote:

> Maybe it means you need one of these:
>
> http://www.amazon.com/SCS-formerly-Static-Control-Economy/dp/B013J8CM6O/ref=sr_1_3?ie=UTF8&qid=1459539400&sr=8-3&keywords=esd+heel+strap
>
>
> *From:* Josh Baird <[email protected]>
> *Sent:* Friday, April 01, 2016 2:32 PM
> *To:* [email protected]
> *Subject:* Re: [AFMUG] Another ground question
>
> Well - today, I'm not seeing -any- voltage (from my digital multimeter)
> between metal IN the enclosure.  I have no idea why I did yesterday,
> because nothing has changed.
>
> I do see a little bit of DC voltage when I hold the black lead in my hand
> (lead touching my hands) and put the red lead on various metal pieces in my
> enclosure.  No idea why this is, but I don't think it's something I should
> be concerned with, right?
>
> On Thu, Mar 31, 2016 at 6:44 PM, Ken Hohhof <[email protected]> wrote:
>
>> If the two pieces of metal are not connected together, like if one of
>> them is floating except for stray high resistance paths to ground, then I
>> wouldn’t pay much attention to the voltmeter reading.  Especially if you
>> are using a high impedance digital meter.
>>
>> Or if they are connected via a wire carrying high current, 0.1 volt may
>> not mean much.  If you have 10 amps flowing through a wire with 0.01 ohms
>> resistance, there’s your 0.1 volt.
>>
>> If that second piece of metal is grounded to your common ground point
>> with a wire that should not be carrying any current, then I might worry
>> about the 0.1 volt.  You might have a ground loop.
>>
>> Are you seeing a DC or AC voltage?
>>
>>
>> *From:* George Skorup <[email protected]>
>> *Sent:* Thursday, March 31, 2016 5:32 PM
>> *To:* [email protected]
>> *Subject:* Re: [AFMUG] Another ground question
>>
>> That's what i was going to say. If it's a cheap meter, don't worry about
>> it. Bond everything and you should be fine.
>>
>> On 3/31/2016 5:27 PM, Chuck McCown wrote:
>>
>> Depends on the meter.  Does the meter read 0.0 when the leads are shorted
>> together?
>> Some meters have some random fluctuations in the least significant digit
>> all the time.
>>
>> *From:* Josh Baird <[email protected]>
>> *Sent:* Thursday, March 31, 2016 3:24 PM
>> *To:* [email protected]
>> *Subject:* [AFMUG] Another ground question
>>
>> I'm working on a new DC enclosure (steel 19" rackmount cabinet).  When
>> using a DC volt meter, and putting the 'red' lead on a common ground point
>> (my ground bus, a metal rack rail, etc), and the 'black' lead on something
>> metal, I'm seeing ~0.1V.
>>
>> I'm assuming this is bad.  On the bench currently, I have the AC ground
>> connected to my PSU.  I have all other devices (switch, surge suppressors,
>> rack rails, etc) tied to a common ground that isn't yet connected to
>> earth.  My PSU and power distribution is on a metal DIN rail which in turn
>> is mounted to the metal rack rails.
>>
>> Should I be concerned with this?  As much as I try (or not), I still have
>> trouble wrapping my head around ground/ground potential/etc.
>>
>> Josh
>>
>>
>>
>>
>>
>

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