new UV sensor behaving oddly

[geoff]

I've recently installed one of the new UV sensors. The graph below shows data plotted on 2 min intervals so far today. It is typical. Notice the "spikes" one of two each hour. There is no obvious explanation for this, the sensor is in full sunshine right next to my hobby-boards solar sensor which shows a smooth curve as the day progresses. Note that the spikes occur during the night too ...

Any ideas ?

 

[ericvic]

Not sure what might be causing those spikes. In our testing we didn't see any spikes like that.

What software are you using?
How are you powering the UVI Meter?

Eric

 

[geoff]

Not sure what might be causing those spikes. In our testing we didn't see any spikes like that.

What software are you using?
How are you powering the UVI Meter?

Eric

Power is 16v from one of your hubs. The sensor is physically close to one of your solar sensors and a AAG weather station (on the same wire). The other sensors behave as expected. Are you thinking that maybe the power is "dirty" at the sensor ? The 1-wire does run alongside an ethernet cable using POE for maybe 15 metres, perhaps there is some cross-talk? I will try and disconnect the ethernet for a while and see if it makes any difference.

For software I use OWFS as the interface to the 1-wire network and a home-grown perl script to scan round the devices and read/archive the data.

 

[geoff]

Disconnecting the ethernet cable made no difference.