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#145994 - 09/08/06 06:24 AM Voltage warning labeling
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
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).]

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#145995 - 09/09/06 09:46 AM Re: Voltage warning labeling
djk Offline
Member

Registered: 12/26/02
Posts: 1269
Loc: Ireland
"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).]

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#145996 - 09/10/06 05:46 AM Re: Voltage warning labeling
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
 Quote:
"If you value your fingers, do not insert here"


I like that one!

 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."

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#145997 - 09/19/06 07:41 PM Re: Voltage warning labeling
tajoch Offline
Member

Registered: 02/09/01
Posts: 53
Loc: Quinlan texas, usa
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

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#145998 - 09/20/06 04:42 AM Re: Voltage warning labeling
Kenbo Offline
Member

Registered: 04/07/06
Posts: 234
Loc: Scotland
I can not explain this label.

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

I £$%^& well hope so that is why we bought them.
_________________________
der Gro├čvater

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#145999 - 09/20/06 07:22 AM Re: Voltage warning labeling
Trumpy Offline

Member

Registered: 07/05/02
Posts: 8540
Loc: SI,New Zealand
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?.
_________________________
Let's face it, these days if you're not young, you're old - Red Green grin

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