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PostPosted: Sat Oct 11, 2014 9:46 am 
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Just a few comparisons:

Telensa - Base station range 2-3km (urban)/5-8km (rural), up to 5000 nodes per base station

Mayflower - Submaster range 200m (???), up to 250 nodes per submaster

Zodion Vizion - Collector range up to 3km, up to 250 nodes per collector

Harvard LeafNut - Branch node range up to 1km (urban), up to 256 nodes per branch node

It isn't difficult to see how the Telensa system has taken off more rapidly than competitors' systems, given its range and capacity. Reliability wise, my observations suggest that the Telensa and Mayflower systems are the most reliable. With both the Zodion and Harvard systems I have seen high proportions of dayburners.


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PostPosted: Sat Oct 11, 2014 10:39 am 
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Thanks for the info - interesting stuff.

Presumably, if RF control becomes more widespread, one may have to take the noded lantern a fair way to be out of reach of the local network, although I too suspect the CMS is not simply "plug & play". Whilst not being electronically blessed, I assume the systems are unlikely to interfere with each other, for example on neighbouring local authority borders which may be using two different systems.

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PostPosted: Sat Oct 11, 2014 10:54 am 
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With earlier systems there was possibly the chance of interference between neighbouring authorities if using the same system. Telensa makes a point about different authorities being able to keep their systems separate even though within range of each other, and given the barcode system of Mayflower I suspect interference is no problem with these either.

In south Hampshire we have the South Coast PFI (Southampton and Hampshire) using Mayflower nodes, the Highways Agency using Zodion nodes, and also an experimental stretch of older generation Mayflower nodes in Portsmouth which may or may not still exist.

The old generation Mayflower system experimentally used in Portsmouth was interesting. I didn't spot a submaster node like the current system, although I'm sure a base station must have existed in some form. At switch on time the lanterns in the road switched on in sequence rather than all at once, with a time delay of near enough a second between each switch on. Hence, you saw the awakening lights coming towards you! It was as if the system relied on neighbouring nodes communicating with each other in a daisy chain.


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PostPosted: Sat Oct 11, 2014 9:31 pm 
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sotonsteve wrote:
The old generation Mayflower system experimentally used in Portsmouth was interesting. I didn't spot a submaster node like the current system, although I'm sure a base station must have existed in some form. At switch on time the lanterns in the road switched on in sequence rather than all at once, with a time delay of near enough a second between each switch on. Hence, you saw the awakening lights coming towards you! It was as if the system relied on neighbouring nodes communicating with each other in a daisy chain.


The fledgling Mk1 Mayflower system used a base station setup which could be building mounted (i.e. depot/council office) and due to hills etc also used repeater aerials which had no necessity to be connected directly to the columns that they were mounted on.
The nodes themselves had to be programmed on the system in the order that they appeared on the street. So as Steve says, they signal would 'bounce' from node to node down the street in a set sequence. A flaw in that system means gap of 3 or more nodes in the chain (e.g. dead service) would stop the chain and the nodes upstream would not be reached.
The new systems use nodes which individually communicate with the master/branch/collector and so alleviate the possibility of this problem.


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PostPosted: Sun Nov 02, 2014 7:48 pm 
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A replacement column and lantern in my village was commissioned this week, however the lantern is fitted with a Telensa RF node. I was expecting the lantern to dayburn - loss of signal to node - but it is switching correctly.

My village is about 3 miles/5 km from the closest other nodes in Salisbury. There is also a 100m hill between my village and those nodes.  The basestation is also likely to be in the centre of the city adding potentially a couple more miles in range.

Telensa quote 5-8km coverage in rural areas.

However the lighting in my village is fitted with part night NEMA cells.The new lantern is running all night. A query to Wiltshire council to have the node reprogrammed for part night was met with this response:

Quote:
Ordered and fitted incorrectly with Telensa CMS control, should have been part night cell. Firsdown too far away to communicate with Salisbury stations. Passed to contractor for rectification and fitting of PN cell.


So despite working at the maximum theoretical range for the Telensa system, the node will be replaced.

It also seems to indicate that the coverage of the Telensa system won't be extended to cover our 50 or so streetlights and that we will retain our legacy part night system.


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PostPosted: Sun Jan 18, 2015 10:44 am 
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The Mayflower system used by the south coast PFI has had instances where streets have failed occasionally to switch on. There was another instance of this in Winchester last night with several streets unlit apart from one or 2 lanterns.

With the Harvard system, loss of node connectivity causes a dayburn, the same doesn't always seem to be the the case for Mayflower. More worryingly, the monitoring system does not seem to be robust enough to self detect normally lit streets have failed to light by checking that nodes are "reporting in" - or not in this case. Of course, the error log may not be checked till Monday....


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PostPosted: Sun Jan 18, 2015 10:51 am 
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There is also the peculiar situation of a Mini Luma in the village of Twyford near Winchester. One lantern in the village stays on in the morning long after all the others have switched off, and in the evening it switches on much later and after dark.


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PostPosted: Wed Jan 21, 2015 7:32 pm 
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The Harvard and Mayflower systems are known to be able to control lanterns down to an individual unique lantern if required, although it is more common to control to street level, or groups of streets.

The master nodes for these systems are physically different to the slaves, so its fairly easy to spot the masters and the number of them, although geography and obstructions will determine the actual number of master nodes and their range.

Less is known about Telensa system, although the manufacturer quotes that up to 5000 nodes can be controlled by a single master.

Looking at the Telensa system installed in Salisbury, I have yet to find the master node(s) - the aerials and associated control boxes - there appear to be less of them for a given area compared to the Harvard and Mayflower system. If coverage of the Telensa masters is comparable to the competing systems, I would have expected to find at least 6 of them in the city.

Today I was driving through the city at switch on time and it was interesting to observe how lanterns switch on. Salisbury still has quite a bit of residential, and to a lesser extent, main road SOX. The slow warm up time is very useful for tracking the order of when lanterns turned on - not really possible with SON and impossible with LED.

Whilst some blocks of residential streets had all their lanterns switch on together, this wasn't always the case. There were areas where only some lanterns in the street switched on together - others in the street remained off. Residential streets switched before the main roads which had Telensa nodes fitted - some main roads are under control of the HA and have conventional NEMA cells.

On the main roads, roundabouts would be on, but the roads feeding them would be off, or vice versa.

So it appears, that the Telensa system does allow a fair degree of lantern control, possibly down to individual lanterns, despite using less master nodes than Harvard or Mayflower. It also appears that in Salisbury, geographic block by block switch on hasn't been implemented, but instead a more selective switching scheme.

It would be interesting to know how switching has been implemented in other Telensa schemes.


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PostPosted: Wed Jan 21, 2015 7:39 pm 
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Telensa uses an aerial and junction box mounted as a bolt-on accessory to an existing column as opposed to master nodes on lanterns.


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PostPosted: Wed Jan 21, 2015 8:36 pm 
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Yes, I am fully aware of that, but from a system point of view, the aerial is still considered the master control point for all the slave nodes that are controlled by it - all control functions emanate from that point. The aerial of the Telensa is no different in functionality to the Harvard or Mayflower master nodes.


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