Quote from: picowatt on May 06, 2012, 10:21:59 AM
I have never cut a ground pin off the end of an AC cord.  When I do need to lift an AC ground, in the US we have adapters that allow isolation of the AC ground (they were not originaly intended for this purpose, but they work well for AC gnd isolators).  If I do need to maintain an AC gnd on bench equipment (which I usually do thru at least one path), there are other methods that can be used related to the power and signal common ground scheme that can ensure there are no "loops".

Possibly in SA there are no adapters available that allow easy isolation of the AC ground.  If this is so, and you do need to isolate an AC ground, you can make an extension cord from individual AC connectors and power cord and not hook-up the AC ground at one end.  This method would be particularly suitable for equipment that has a fixed, non-removable AC line cord.

However, most newer equipment, including the LeCroy,  use a standard IEC connector with a country specific AC connector at one end.  You could purchase a few new IEC cords suitable for SA and cut the AC ground pins from these new cords.  You could then use these cords whenever you need to isolate equipment that has an IEC connector.  Also, if it is necessary to isolate a piece of rental equipment, you can use one of your new isolated cords, leaving the original cord intact.

PW

I have NO intention of cutting the ground pin.  You really do go to EXTRAORDINARY lengths to trivialise my intelligence.  On loan I would NEVER subject the LeCroy to the risk of applying it without ground.  It does not have the grounding features of the Tektronix.  I am prepared to do this while the instrument is in my ownership.  And then I'll be applying it with reasonable protective measures.  Otherwise iIt would be in contravention to our loan agreement where it's use is contracted to safe practices

Rosemary

Quote from: TinselKoala on May 06, 2012, 09:25:23 AM


And just how, exactly, does an official calibration laboratory DO that magic "calibration" stuff anyway, I wonder?

   


(They are just questions, Leon.)

Leon - that's so much better than TK.  Is that your name?  I've always wondered.

The calibration labs compare the performance measurement to proven values.  Your own calibration exercise in standardising your measurements were a joke.  I gave you the example.  You can calibrate your watch to Greenwich Mean Time.  You cannot calibrate it to synchronise with your neighbour's watch.  What you did was calibrate it to ?  I'm not sure which of your instruments.  They are all as likely to be as faulty as the next.

Rosie Pose

Quote from: Rosemary Ainslie on May 06, 2012, 03:27:19 AM
Then.  In order to use the LeCroy without the 'ground pin' - which is to satisfy you that we do NOT have grounding issues - I've been obliged to buy that instrument.

Excuse me!

Geesh,
PW 

Rosemary,

Do you even use a third chassis connected ground conductor in SA for your AC distrib system?

Some countries don't.

PW

Quote from: picowatt on May 06, 2012, 01:06:58 PM
Rosemary,

Do you even use a third chassis connected ground conductor in SA for your AC distrib system?

Some countries don't.

PW

Never mind, looks like you do in SA.

I've rented plenty of equip over the years and never gave a second thought to floating the ground when necessary.  Never had a problem. 

PW