Doing some more digging on line, there are 3 generations of the Telecell.
1. Spike housing. CMS communication via master node, no daylight sensor, no GPS. No dimming.
2. Dome opaque housing. CMS communication via master node, in built GPS and I presume as the dome is not transparent, no daylight sensor. Dimming via DALI or analogue voltage.
3. Dome clear housing - as my last post. Latest generation. CMS communication via master node, in built GPS and daylight sensor. Dimming via DALI or analogue voltage.
Type 1 will only switch via CMS communication.
For Type 2 and 3, when first powered on, they will dayburn for 50 secs then turn off. If connected to a dimming ballast, they will run the ballast at full power for 25 secs, then dim for 25 secs and then switch off.
After 15 mins, if the node hasn't established comms with the CMS (which can take several hours) and no GPS fix has been established, the node will turn the lamp on.
If a GPS fix has been established, the node will act as a normal dawn/dusk photocell. For Type 2 node, GPS time must use a solar map look up table, to establish local dawn and dusk times.
For Type 3, I suspect GPS/solar map is the primary reversion mode, but backed up by the photocell. This would explain why these nodes are working perfectly well in rural areas of Wiltshire where the CMS doesn't exist yet.
This multi-switching arrangement also has the benefit that dawn dusk operation will still occur prior to the nodes being mapped to the CMS, eliminating (often) days of dayburning that occur with other systems.
If Hemel tries his node without the crisp packet and leaves it powered long enough, it will probably switch off during daytime hours - but using GPS.
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