Function generator outputs are connected to earth?

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It would be pretty unusual to have a full floating f() generator, or so I think. I dont
see a differential marked pair of BNC out.

Measure ohms between bnc shell and line neutral of its line cord.

You could use an AC line isolation transformer to achieve some semblance of floating, but
datasheet/manual may not spec common mode limits which you could violate depending
on how it was designed and fry it and/or whatever its connected to.
 
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Not a very useful datasheet, it doesn't even give a picture of the back of the unit

Does it have a three core mains lead or a two core one?, as it's in a plastic case it's likely to be a class-II device with a two core mains lead, so no earth. Such devices are often two core, if it's three core them measure from the earth pin to the BNC sockets see if it reads between them, if it's earthed it will be low resistance.

I wouldn't measure from neutral to BNC, as it shouldn't be connected to neutral.
 
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Externet said:
If the chassis is connected to the power cord 'ground' green conductor; is the BNC symbol both ground, common and chassis ?... And mains neutral too at the breaker box ?

How is the european ground at the breaker box ? Attached to neutral also ?
Click to expand...

You're assuming it has a three core mains lead?, it's more likely a class-2 device, double insulated with no earth lead. As the front symbol is chassis, it's another potential indication that it's only a two core lead?.

But the datasheet in the OP is completely useless, and tells you almost nothing. However, the instruction book isn't much better (no pictures or diagrams), but it does say "WARNING! THIS INSTRUMENT MUST BE EARTHED", and a lot of searching finds a reference to it being class-I.

I can't comment on Europe, but in the UK earth is either a local mains spike, or connected to neutral, and earthed at the sub-station transformer.
 
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On the right side, below the centerline is a switch labeled GND / FLOAT. It looks like this gives you the option of connecting the internal signal ground to the chassis / earth ground.

ak
 
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It seemed obvious to me , so I had to find proof. p.7 https://resources.aimtti.com/manuals/TG550_Instruction_Manual-Iss9.pdf

"Any interruption of the mains earth conductor inside or outside the instrument will make the instrument dangerous. Intentional interruption is prohibited. The protective action must not be negated by the use of an extension cord without a protective conductor"

Yes, you can disconnect at your own peril during a thunderstorm or measure the stray leakage in the transformer with your hand on PE. Possibly, they intended you to want an external PE to avoid a ground loop on the DUT. Hence the CYA legalese.
 
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I would assume that the OP would know if the instrument's power plug had two or three pins, and that if it had only two pins, that they wouldn't have needed to ask the question.
 
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Unable to magnify the image of its power cord to see if has ground terminal But the next image shows a warning... and that IEC cord is a clue...
-Images borrowed from the web-





By the way. My instrument at post #5 is powered by an ungrounded wall adapter transformer. Mains to ---> 14VAC two conductors. No ground plug at the power cord, no neutral either, and not even mains phase/live/hot 120VAC. Just from a secondary AC winding
 
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Externet said:
Unable to magnify the image of its power cord to see if has ground terminal But the next image shows a warning... and that IEC cord is a clue...
Click to expand...

Not much of a clue, as the IEC mains connector is available as either two or three pin

What we needed was a picture of the back of the unit without the mains lead plugged in, to see what the socket is - although it's 'probably' a three pin one.

Incidentally, while you can put a three pin lead in a two pin socket (because it's obviously safe to do so), you can't put a two pin lead in a three pin socket (because that would remove the earth. For that reason the two pin plug and socket has an indexing protrusion to prevent the two pin lead going in a three pin socket.
 
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Treez lives in UK, where most IEC cables are three pin with ground.

I would bet odds of 10 to 1 that Chassis is connected to ground for UK version.

Do not own that particular instrument (but really wish I did) to be 100 percent sure.
 
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