How long was your 'Longest Day'?

[wildebus]

Today (June 21st) is meant to be the longest day, and curious to know how long your own Solar Harvesting day was?

For those who can tell (e.g. @St3v3 , @RAW and maybe others), post the time your MPPT Controller turned on this morning and went off this evening - and your location (to get an idea how north you are).

My controller - around Coldstream - went on at 04:49 and off again at 22:05 - a day of 17.25 Hours.
Another system I can monitor in Aberdeen went on at 04:21 and off at 21:47 - 10 minutes longer as further North (and an earlier start and finish as further east)

How do yours compare?

 

[Nick-Mandy]

10 hours too short

 

[Admin]

It is a leap year so the longest day was the Saturday 20th in 2020.

 

[wildebus]

10 hours too short

Where are you to have a SOLAR day 27 hours long?

 

[wildebus]

It is a leap year so the longest day was the Saturday 20th in 2020.

An interesting point
I just checked Saturday ... 4:45 (4 minutes sooner) start and end was 21:55 (10 minutes earlier). Could be cloud cover?
I could check the weather station as that has info as well from the solar irradiation sensor.

The main thing I was interested in was not what was the longest of the year but actually how the lengths change as you go further south. What are your start and stop times for the 21st?

 

[jagmanx]

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20 and 21 almost identical
but 20th by a "shorthead"

 

[jagmanx]

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or for @linkshouse

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[Wooie1958]

It is a leap year so the longest day was the Saturday 20th in 2020.

Ah, that`s the reason, i`ve felt rubbish all weekend so couldn`t be bothered looking into it

 

[linkshouse]

Sunrise and sunset times in Thurso

Calculations of sunrise and sunset in Thurso – Scotland – United Kingdom for October 2025. Generic astronomy calculator to calculate times for sunrise, sunset, moonrise, moonset for many cities, with daylight saving time and time zones taken in account.

www.timeanddate.com

or for @linkshouse

Sunrise and sunset times in Westray

Calculations of sunrise and sunset in Westray – Scotland – United Kingdom for October 2025. Generic astronomy calculator to calculate times for sunrise, sunset, moonrise, moonset for many cities, with daylight saving time and time zones taken in account.

www.timeanddate.com

It doesn't look like my controller gives the actual start and end times but here are screenshots of delivery totals for yesterday and the day bfore -





It was bit of a misty start for both days, in fact we seem to have had misty starts to what have turned outo be glorious days for a wek or so.

Regards

Phill

 

[trevskoda]

No such thing as a longest day as there all 24hrs long.

 

[Wooie1958]

No such thing as a longest day as there all 24hrs long.

Trev, when the clocks go forward that day is 23 hours long and when they go back that day is 25 hours long

 

[St3v3]

0600-2115hrs on the 20th

I suspect the truck is probably in shadow really early though

 

[wildebus]

Sunrise and sunset times in Edinburgh

Calculations of sunrise and sunset in Edinburgh – Scotland – United Kingdom for October 2025. Generic astronomy calculator to calculate times for sunrise, sunset, moonrise, moonset for many cities, with daylight saving time and time zones taken in account.

www.timeanddate.com

20 and 21 almost identical
but 20th by a "shorthead"

There is sunrise and sunset. There is also dawn and dusk. A different thing. I want to know about "Victrons", a different measurement standard entirely

 

[jagmanx]

Yes a bit like a piece of string with knots near the ends and then the string is fraying !

 

[wildebus]

It doesn't look like my controller gives the actual start and end times but here are screenshots of delivery totals for yesterday and the day bfore -

View attachment 54877

View attachment 54878

It was bit of a misty start for both days, in fact we seem to have had misty starts to what have turned outo be glorious days for a wek or so.

Regards

Phill

I am guessing you are further north than I am

The Victron has no idea of time of day so you can't get that info. You can get the times if you have a Victron Venus system the controller is connected to though.

FYI . (if you cared?), the day is assumed to start with a Victron Controller when the controller sees no light on the panels for more than an hour. SO if you say parked in a very dark area in the some time in during daylight hours every day, you would end up with twice the amount of "solar days". If you parked where it was light enough for the panels to activate sufficiently overnight, I guess the day could be over 24 hours? (I don't know if it has a counter that will reset to the next day if it hits 24 hours of being on?)

 

[linkshouse]

I am guessing you are further north than I am

The Victron has no idea of time of day so you can't get that info. You can get the times if you have a Victron Venus system the controller is connected to though.

FYI . (if you cared?), the day is assumed to start with a Victron Controller when the controller sees no light on the panels for more than an hour. SO if you say parked in a very dark area in the some time in during daylight hours every day, you would end up with twice the amount of "solar days". If you parked where it was light enough for the panels to activate sufficiently overnight, I guess the day could be over 24 hours? (I don't know if it has a counter that will reset to the next day if it hits 24 hours of being on?)

I’m on Westray, one of Orkney’s northern isles.

Phill

 

[xsilvergs]

This is for Saturday and Sunday, location south coast of England.
Saturday: Victron 100/30 MPPT turned ON at 04:05 and OFF at 22:00 ish
Sunday: Victron 100/30 MPPT turned ON at 04:15 and OFF at 22:10 ish
MPPT Charge Status: 10 = Bulk, 7.5 = Absorption, 5 = Float, 2.5= OFF, 0 = Fault
Solar Battery Amps is the current going into the Leisure Battery, this is less than the Amps from the panels as there are a few drains, RPI, Router etc. Unfortunately the Amps from the panel isn't shown.
There is only a single 100 W Solar panel connected.



The Starter Battery is charged from the Leisure by an Ablemail AMT Battery Maintainer

 

[wildebus]

Interesting graphs I can see on the Starter Battery Volts graph when the AMT-12 is kicking on after the solar starts up

 

[xsilvergs]

Interesting graphs I can see on the Starter Battery Volts graph when the AMT-12 is kicking on after the solar starts up

Yes the AMT-12 does what it says on the tin (as they say), it's nice that should it ever have a problem it's easy to isolate, something you can't do with combined units.

Watching the status LED when the Starter Battery approaches/is charged shows how it misses out unnecessary charge pulses. I haven't got around to data logging from it yet although I doubt it will be very interesting.

 

[wildebus]

Yes the AMT-12 does what it says on the tin (as they say), it's nice that should it ever have a problem it's easy to isolate, something you can't do with combined units.

Watching the status LED when the Starter Battery approaches/is charged shows how it misses out unnecessary charge pulses. I haven't got around to data logging from it yet although I doubt it will be very interesting.

If you can reprogram and fine-tune it, it could be useful potentially for other things (not sure what exactly, but bound to be something PS. Speaking to Jonathan last week and he said he found what you are doing very interesting indeed )