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Posted By: pauluk U.K. Pics: Service drops - 07/12/02 10:20 PM
Here is a typical older-style overhead service with two lines:
[Linked Image from members.aol.com]

It's not clear from the photo, but in this case the upper line is the neutral and is bare.

Newer overhead drops use a single cable with concentric neutral (and outer PVC sheath). This one has clearly been converted from an older-style drop (note the spare porcelain insulator):
[Linked Image from members.aol.com]

And here's an wider view:
[Linked Image from members.aol.com]

This particular pole has only 2 of the 3 phases run to it (entering top left) and feeds four houses -- Two newer concentric cables going to the right, one older twin-cable drop to the left, plus one underground service. The thin line farther down the pole is telephone.



[This message has been edited by pauluk (edited 07-12-2002).]
Posted By: Trumpy Re: U.K. Pics: Service drops - 09/20/02 06:04 AM
Paul,
Why does the UK use, the vertical orientation of the lines on the pole, as opposed to using cross-arms?.
Also, do you guys still have the fuse that protects the consumers installation at the meter-board?.
Posted By: pauluk Re: U.K. Pics: Service drops - 09/20/02 06:55 PM
Why a vertical orientation? I'm afraid I have no idea! All the 240/415V distribution that I can ever recall seeing was done this way.

The 11kV and 33kV distribution is arranged horizontally on cross-arms, as you can see in some other photos.

I can only guess that the vertical arrangement just grew up as a convention, or maybe somebody figured it would save materials by not having to use cross-arms.

What arrangement of conductors do you use in NZ?

Yes, we have a main fuse (owned and sealed by the power company) fitted on the board just ahead of the meter.

Have a look here .


[This message has been edited by pauluk (edited 09-20-2002).]
Posted By: Bjarney Re: U.K. Pics: Service drops - 09/20/02 10:41 PM
You right-o’-ponders have one thing I wish left-side folks have—the ability to test receptacles without special, ‘choked-down’ probes.

Compare: http://www.fluke.com/products/home.asp?PID=9493 4mmØ—same size as universal "banana" probes, for IEC-style receptacles.

To: http://www.fluke.com/products/home.asp?PID=9485 ~1.5x3mm—"sloppy" probes for US receptacles.

{Grass always seems greener on the other side of the fence.}
Posted By: pauluk Re: U.K. Pics: Service drops - 09/21/02 08:00 AM
It's not quite so easy with modern British outlets though, because you have to open the shutters first. The technique I use is:

Probe in right hand goes into ground (top) hole at a slight angle, then press it down to open the shutter. Probe in left hand into neutral hole (lower left) and keep downward pressure to hold the shutter open while first probe is removed from earth pin. Transfer probe in right hand to hot contact (lower right). If I then need to measure hot-to-ground, it's easy to transfer the probe in my left hand back to the ground contact. It takes much longer to describe than to actually do it!

That works on all the original-style shutters which are operated by a pin in the ground hole, but some of the newer shutters work a different way. The new MK shutters rely on equal pressure on the hot and neutral shutter to release it and have it turn slightly to uncover the holes. For those, you have to place the probes for neutral and hot at the appropriate holes, one at the top left of the hole, the other at the bottom right of its hole, then gently apply equal pressure.

I hear that MK is going to manufacture a new shutter mechanism which will require pressure at all three entrances to open.

Still reckon the grass is greener? [Linked Image]


[This message has been edited by pauluk (edited 09-21-2002).]
Posted By: Bjarney Re: U.K. Pics: Service drops - 09/21/02 04:13 PM
Should have said "grass looks greener." smirk After your description, I need some aspirin.
Posted By: Roger Re: U.K. Pics: Service drops - 09/21/02 05:23 PM
Paul and others, I may be off base here, but our child proof or safety receptacles also incorporate shutters that must be triggered (lack of better term) to open.

If we are checking or trouble shooting a circuit, we use an adapter or cord cap to speed things up.

Paul, does the cable in the second picture just enter into the wall as it appears?

Roger
Posted By: Bjarney Re: U.K. Pics: Service drops - 09/21/02 05:36 PM
Have a couple of old "cheaters" for checking 'merican plugs .
Posted By: pauluk Re: U.K. Pics: Service drops - 09/21/02 05:55 PM
The MK catalog here actually lists shuttered outlets to NEMA 5-15 configuration, although they are on plates which fit standard British fixture boxes. (Sold for export to some Middle East countries.) I'm not sure how the shutters work on those.

Yes, the cable in the second picture just goes through the wall to the main fuse and meter inside the house.
Posted By: Roger Re: U.K. Pics: Service drops - 09/21/02 05:57 PM
Bjarney, your's are really sophisticated compared to our versions. [Linked Image]

Roger
Posted By: Bjarney Re: U.K. Pics: Service drops - 09/21/02 06:57 PM
Roger — About the fancy cord with the shrouded banana plugs in the picture…I forgot to return it with a rental power-transient recorder. They back-charged me $80 for it. Note the “safety” color-coded 5-way binding posts on the other one…the pins are not polarized!
Posted By: Roger Re: U.K. Pics: Service drops - 09/21/02 09:27 PM
Whoa, $80.00, [Linked Image] I bet you'll consider my low tech version next time. [Linked Image]

Roger
Posted By: Bjarney Re: U.K. Pics: Service drops - 09/22/02 02:24 AM
Yes, you can imagine my surprise. That was apparently the instrument-rental outfit’s "standard minimum" late/missing charge for non-returned accessories. When I saw the added amount on my credit-card statement, I offered to promptly visit the sales droid and firmly place the cord in a spot where he would have no problem finding it, but was told that such an act would not eliminate the charge.




[This message has been edited by Bjarney (edited 09-21-2002).]
Posted By: pauluk Re: U.K. Pics: Service drops - 09/22/02 02:19 PM
80 bucks!!! I bet you're really careful about making sure all accessories are returned now, aren't you? [Linked Image]
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