Using Twin-BNC connector for commercial power 4

[VEBill]

Yikes. I thought I had seen everything.

A certain company that shall remain nameless, is using Twin-BNC connectors (just like a normal BNC connector, except with TWO conductors in the middle: an exposed pin and a somewhat insulated socket) to connect an external power source to a load within their product.

(Amphenol P/N 31-224, intended for RG-108A/U cable)

I figure that misusing a BNC-type connector like this would be fine for low voltage DC. But they offer the same system with a 240VAC requirement (!) for example.


My view is that using this sort of connector for anything above low voltage (like 28 VDC) is so rife with safety violations that there is absolutely no way that it could ever be permitted.

Any alternate views on this issue? Am I missing something? Would it ever be permitted? (Location is in Canada in case that matters.)

Thanks.

 

[MacGyverS2000]

It would never pass UL having an exposed conductor that carries such a high voltage AC (like having the male plug sticking out of the wall instead of a female socket), and I find it hard to believe CE would even consider it, either. I take it neither of these marks is on the product?

Dan - Owner

http://www.Hi-TecDesigns.com

 

[VEBill]

CSA (Canadian Standards Assoc.) is the rough equivalent to UL. Although I already know the answer, I've asked if their product is CSA or equivalent approved.

The only available (as far as I can see) mating connector for the field-installed wiring is designed for RG-108A/U twinaxial cable. With 20-ga conductors. Not really intended for commercial power...

Not to mention, the product is for outdoor use only. In the humidity & condensation, and maybe even the rain...

 

[dpc]

I just saw the same thing on a small "industrial" comm processor/port server. It was for dc power supply in this case. When I first saw it, I thought it was an antenna connection.

If no UL mark, it would be a problem in the US, I would think.

 

[mcgyvr]

Voltage rating of twin BNC = 100 volts peak
It better not be approved by any standards agency.. But I wouldn't be suprised.

 

[VEBill]

I wouldn't mind using it with (say) a 28 VDC power supply with an appropriate current limit. The system only needs 9 watts. But these guys also offer 120VAC, 240VAC, and 277VAC options, all apparently using the same connector (!).

If we have no choice, then we will use the low voltage DC option to avoid all the obvious risks, but this means we have to add a power supply into what would have otherwise been a very simple system.

It would have been so much easier to just connect the product to a normal 120 VAC commercial power source, if only they hadn't decided to use an inappropriate connector.

 

[ScottyUK]

Makes you wonder what else they didn't engineer properly... you can't seriously be using that for mains voltage applications! Are you sure they don't provide an external power supply or a wall wart with the mains voltage units?


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If we learn from our mistakes I'm getting a great education!

 

[VEBill]

"Are you sure they don't provide an external power supply or a wall wart with the mains voltage units?"

Yes, they don't.

The subsystem at the top can be selected to use either low voltage DC (my preference), or the 120, 240, 277 VAC options. All powered via the Twin-BNC connector at the bottom end of the assembled product.

They really should, for the higher voltage options, just drill out the connector mounting hole and let the (appropriate and approved) power cable emerge in a 20-foot long pigtail to be terminated by the electrician.

 

[mcgyvr]

Well if the unnamed company is worth buying from they would happily change to a more suitable connector if you informed them of your issues/concerns.
I wonder if this is just an issue of you assuming they use the same connector...
Skotty is right though about who knows what else they didn't engineer properly.. I would look elsewhere for whatever it is you need from them as they obviously don't know what they are doing.

 

[VEBill]

I'm in discussions with them. But they are struggling to comprehend what I'm going on about. When I asked about CSA (UL-type safety) approval, they offered up FCC references.

The issue is genuine - for example, when I asked about the exposed pin in the power side connector, they suggested that the 'Neutral' be wired to that exposed pin in the connector.

 

[mcgyvr]

No matter how its wired, anything over 100V on that connector violates its approved rating.

FCC doesn't care about safety.

 

[VEBill]

Thank you one and all.