Cumulus Support

Yes, thanks, but can I rely on the console data to correctly reflect Imperial readings?

As discussed, the UK spec Vue is configured for metric rain readings.

Sunfish wrote:Yes, thanks, but can I rely on the console data to correctly reflect Imperial readings?

As discussed, the UK spec Vue is configured for metric rain readings.

I've already made assumptions about the Vue and been wrong, so I'm probably the wrong person to be attempting to answer this question. But I would assume that if the console has an option to display in imperial, then it will correctly convert the 0.2mm rain gauge tips into inches and apply some kind of rounding - the VP2 displays correct figures in either imperial or metric independently of whether the gauge has the metric adapter fitted or not.

Is there a setting in the Vue console to tell it which type of rain gauge it has fitted?

steve wrote:Is there a setting in the Vue console to tell it which type of rain gauge it has fitted?

Steve, here is are some quotes from the Vantage Vue documentation:

• --------------------------------
  Screen 13: Rain Collector
  
  The tipping spoon in the Vantage Vue rain collector has been calibrated at the factory to measure either 0.01'' or 0.2mm of rain with each tip depending on the model. This screen is used at the factory for this calibration. The typical user will not need to change it and can skip this screen.
  
  Note: This screen will not change the units on your display. To change the units on your display from inches to mm, or vice versa, see “Selecting Units of Measure” on page 26.
  --------------------------------

Contrary to the Vantage Pro2, it appears that the Vantage Vue is shipping from the factory (Davis in California??) with either a 0.01 inch 'tipping spoon' or a 0.2 millimeter 'tipping spoon' - 'technically', the Vantage Vue does not have the possibility to exchange/replace the 'tipping spoon' ... I have done no Internet search to find out if a Vantage Vue replacement 'tipping spoon' was available (I do not need one... )

But, going through the setup on my Vantage Vue console, I was able to select (choose) either the 0.01" or 0.2mm option on the 'rain collector' screen - but, that could be because my Vantage Vue is getting its data from my Vantage Pro2 Plus ISS...

I do not know why Davis Instruments has decided to make the rain collector of the Vantage Vue an 'either' buying option (either a 0.01" or a 0.2mm 'tipping spoon') - they could have easily sold/made available (at a slightly inflated price) a replacement 'tipping spoon'...

Replacement Vue tipping spoons are a standard spare item:

The 0.01" part is 7345.280 and the 0.2mm part is 7345.319.

(One of the good things about the Vue ISS design is that it's much easier to replace individual parts such as the spoon compared to the VP2.)

This business of rainfall increments can cause a lot of confusion so the note below summarises the situation:

The Vue console (the VP2 is exactly the same) has no way of knowing independently which spoon you have fitted. (eg there are no contacts on the spoon assembly allowing the ISS to sense which version is installed).

All that the ISS measures is the number of tips of the spoon/bucket mechanism (ie it does not and cannot measure the amount of rain directly) and this tip-number is all that passes through the Vue/VP2 data chain. To convert the tip-number to an actual amount of rain, the tip-number has to be multiplied by the increment for the installed spoon, ie 0.01" or 0.007874" (for the 0.2mm spoon).

The increment factor is set in the console settings, ie you choose 0.01" or 0.2mm as appropriate. The correct setting for the installed spoon should be made at the factory depending on whether it's the metric, US etc version, but can also be changed later manually if you should change the spoon type. But note that if you change the increment so that it no longer agrees with the actual spoon installed then your rainfall readings will be wrong by 20-25%.

NB #1: The above just refers to what happens at the console. Typically, software may need to be set to the correct increment independently of the console. Actually the rain increment is nominally passed to software in the archive record ('the rain collector type is encoded in the most significant nibble of the rain field'), although most software doesn't pick up this setting, but not AFAICR in the loop record.

NB #2 The above also just refers to what happens for the measurement/logging of rain data. The units you choose for displaying the rain data on the console are quite a different matter and can be changed at will using the Units button on the console. What is happening for display purposes is that the number of tips is being converted to a rainfall amount by multiplying by the increment currently set to give a rain amount (probably always in inches as a first step I suspect, irrespective of whether it's a US or metric spoon, but it doesn't really matter). And then the inches amount is either displayed directly or converted to a mm value if the display units are currently set to mm. But the underlying tip-number stored remains unchanged.

prodata wrote:Replacement Vue tipping spoons are a standard spare item:

The 0.01" part is 7345.280 and the 0.2mm part is 7345.319.

(One of the good things about the Vue ISS design is that it's much easier to replace individual parts such as the spoon compared to the VP2.)

Well, that makes sense. I was sure I had read somewhere that the 7345.319 part was not user-replaceable.

steve wrote:Well, that makes sense. I was sure I had read somewhere that the 7345.319 part was not user-replaceable.

It couldn't be much simpler actually - just the thumbscrew to undo (from the outside) and then the whole assembly lifts away.

Remember though that on the Vue design the rainfall reed switch is not part of the spoon assembly. It's actually part of the battery holder PCBA! (But which is also easy to replace). So if the reed switch starts to go faulty (which being a reed switch it will presumably typically do after some years of service, although it's a rarity as an issue as yet) then it's the battery PCBA you need (7345.293) and not the spoon mechanism.

John, thank you for the information about the Vantage Vue. Do you have any documentation (or can you point me somewhere) on the steps one must follow to exchange/replace the 'tipping spoon' inside the Vantage Vue ISS - I might not have a Vantage Vue ISS but I like to have as much information as is available.

gemini06720 wrote:Do you have any documentation (or can you point me somewhere) on the steps one must follow to exchange/replace the 'tipping spoon' inside the Vantage Vue ISS - I might not have a Vantage Vue ISS but I like to have as much information as is available.

If you download the Vue ISS manual from the Davis site then in the troubleshooting section at the back (p11 I think) there's a short note about how to remove the spoon. TBH the picture isn't very clear, especially if you don't have a Vue, but it is literally as I described - you just undo a thumbscrew on the underside of the ISS and the spoon assembly comes free and can be lifted away.

I got my Vue from the US so i presume it has the imperial tipping spoon. I have the rain collector set to mm in the settings. Would i be right in saying that all the rain readings i have recorded since i started using my Vue are incorrect? If so is buying the Metric tipping spoon the only fix to the issue or can things be fixed in Cumulus or the settings in the console? Regards

Mike

mickopla wrote:I got my Vue from the US so i presume it has the imperial tipping spoon. I have the rain collector set to mm in the settings. Would i be right in saying that all the rain readings i have recorded since i started using my Vue are incorrect?

Yes, the station will have assumed that each tip is 0.2 mm when in fact it's 0.01 inches, if it really does have an imperial spoon.

If so is buying the Metric tipping spoon the only fix to the issue or can things be fixed in Cumulus or the settings in the console?

You just need to configure the console with the correct rain gauge. You can still display it in mm, it just means that the rain will be multiples of 0.01 inches, suitably converted, so there will be a rounding effect.

steve wrote:

mickopla wrote:I got my Vue from the US so i presume it has the imperial tipping spoon. I have the rain collector set to mm in the settings. Would i be right in saying that all the rain readings i have recorded since i started using my Vue are incorrect?

Yes, the station will have assumed that each tip is 0.2 mm when in fact it's 0.01 inches, if it really does have an imperial spoon.

If so is buying the Metric tipping spoon the only fix to the issue or can things be fixed in Cumulus or the settings in the console?

You just need to configure the console with the correct rain gauge. You can still display it in mm, it just means that the rain will be multiples of 0.01 inches, suitably converted, so there will be a rounding effect.

In fact just checked my original order and it was the US metric version that was ordered for me by my friend. Happy days

Thank god i realized it now.I chose initially metric units in the console(aka 0.2mm for every 0.01") so if i calibrate cumulus rainfall with 1.25 it should be right yeah?? (0.2x1,25=0.25)

katdoc wrote:Thank god i realized it now.I chose initially metric units in the console(aka 0.2mm for every 0.01") so if i calibrate cumulus rainfall with 1.25 it should be right yeah?? (0.2x1,25=0.25)

What type of weather station do you have? Your profile has a Fine Offset.

steve wrote:

katdoc wrote:Thank god i realized it now.I chose initially metric units in the console(aka 0.2mm for every 0.01") so if i calibrate cumulus rainfall with 1.25 it should be right yeah?? (0.2x1,25=0.25)

What type of weather station do you have? Your profile has a Fine Offset.

Davis vantage pro2 us/metric version.i forgot to update my profil