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Posted By: pauluk Voltage warning labeling - 09/08/06 01:24 PM
Here's the situation:

A 4-core SWA cable is going to take both inverter and generator power to a mobile home, with a transfer switch in a closet in the latter to select the feed. (Yes, it's that project again!)

The inverter and generator have no sychronization, so that means that the j-box for the SWA in the equipment shed and the xfer switch in the mobile home could have a potential difference of anything up to 480V RMS depending upon the phase angle.

Would you add extra warning labels about two power sources, unsynch'ed power etc. or just use a "Danger" flash with appropriate maximum voltage warning and leave it at that?



[This message has been edited by pauluk (edited 09-08-2006).]
Posted By: djk Re: Voltage warning labeling - 09/09/06 04:46 PM
"If you value your fingers, do not insert here"

I don't understand why traffic light control boxes over here often have a huge label with "WARNING 230V" (or 220V, or occasionally 240V which is just inaccurate)

It's increasingly seen on a lot of things!

... Saw a warning on an Irish rail hot tap though "Caution water may be hot"
Someone wrote "and wet" beside it!

[This message has been edited by djk (edited 09-09-2006).]
Posted By: pauluk Re: Voltage warning labeling - 09/10/06 12:46 PM
Quote
"If you value your fingers, do not insert here"

I like that one! [Linked Image]

Quote
... Saw a warning on an Irish rail hot tap though "Caution water may be hot"

Must have been from the same guy who decided that a microwave meal needed a warning which says "Caution, product may be hot after heating." [Linked Image]
Posted By: tajoch Re: Voltage warning labeling - 09/20/06 02:41 AM
Dunno, I sat at break one night, and watched a kid (20 something guy) put his lunch in the microwave, and when he carried it back to the table, he spilled it into his lap, and was upset that he spilt the hot soup...........lol
Posted By: Kenbo Re: Voltage warning labeling - 09/20/06 11:42 AM
I can not explain this label.

My wife buys whole almonds for baking
Label says "Whole Almonds" "Caution may contain traces of nuts" [Linked Image]

I £$%^& well hope so that is why we bought them.
Posted By: Trumpy Re: Voltage warning labeling - 09/20/06 02:22 PM
Paul,
Quote
The inverter and generator have no sychronization, so that means that the j-box for the SWA in the equipment shed and the xfer switch in the mobile home could have a potential difference of anything up to 480V RMS depending upon the phase angle.
All I would do, is put a warning sign on the Xfer Switch:

Warning: This switch is supplied by 2 seperate sources, isolate both before removing this cover.

IMHO,
That's all you need do, if a person can't work out the meaning of a sign like this, should they really be attempting to access the wiring within?.
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