Topic: VP2 draining battery stupid fast

[4wd]

My VP2 will be about 4 years old and has been generally OK other than needing a new a T/H sensor, now a more troubling fault - a couple of weeks ago it suddenly stopped transmitting with no warning of low battery, to be fair the battery was about a year old so not that surprising it needed renewing.
A new battery got it going but barely two weeks later it stopped completely again after only the briefest warning of low battery.
The solar panel gets it going through the day and no doubt a new battery would work for a short period again.

To me this seems like a faulty capacitor, so I've taken it down (a standby old Vantage Vue is in its place).
The capacitor looks perfect and the board seems remarkably clean with no hint of corrosion around battery or antenna.
I've ordered a new capacitor from Maplins as they are inexpensive and I should be able to change it myself.

Am I missing any other likely explanation?
Everything to do with Davis VP2 seems so expensive I would be inclined to stick with the Vue if this can't be fixed without major purchases.
A new Vue with no console can run on the VP2 console  and is 'only' £189.

[Aardvark]

sounds like you are on the target,the super cap would be my first thought as well.

[4wd]

Fitted the new capacitor yesterday evening and it started transmitting after about an hour in the window this morning.
It still has the depleted battery in for now so will be interesting to see what happens overnight - still on test in the house.

The tricky bit for an inexperienced solderer is clearing old solder from the holes to push the new pins through.
I have a kit with one of those syringe things in to suck it up, but you seem to need three hands to trigger it quick enough 

[Aardvark]

Fitted the new capacitor yesterday evening and it started transmitting after about an hour in the window this morning.
It still has the depleted battery in for now so will be interesting to see what happens overnight - still on test in the house.

The tricky bit for an inexperienced solderer is clearing old solder from the holes to push the new pins through.
I have a kit with one of those syringe things in to suck it up, but you seem to need three hands to trigger it quick enough 

you are going to need to replace the battery as soon as you are sure the supercap has charged up.   I have a story about the solder sucker bulb.   They are hard to find in town, A city of 350,000 you'd think you would have everything, but sadly no.  So I trot over to Radio Shack and they didn't have one, but one in a mall did, so I drive over there.  I ask for  it and these two teens had no idea , but I spotted it and said I wanted it.   The kid ringing up the ticket asked me what it was, and I explained to him how it was used and he had no idea of what or why to solder something. I explained that, then this other kid looks at me and says " You can also do this"  and he made gestures that you could pick up some powder and spray it into your nose.  I looked at both of them and said " You have no knowledge of what I do for a living, I could be an off duty cop, drug enforcement agent, work for Radio Shack as a corporate spy."   I told them they should never do things that make a reference to drugs or  any illegal.  I paid with cash.  The more I thought of it , the pissed I got. So I wrote the corporate offices and they called back apologizing over and over .  I sheepishly strolled by the store about the same time the next week and the two kids were not at the register, but doing the grunt work and this very cute co-ed was there.  I guess  it helps to do things right. However, I can see why Radio Shack in this town is rarely full of customers.    Thus Endeth The lesson.

[Aardvark]

Oh.. one more.   I noticed on the board that there was a space for a 2nd capacitator,  I was told for areas that had real low light another super cap could be placed there.   I called Davis and spoke to one of their staff. He said he wouldn't recommend the 2nd super cap. So I asked why the port. He said there are things on their units (such as the mystery things on the VP2 console screen that pop up)  that are not in use or that the designers put in.   

I agree that unless one is good at soldering, uses a low heat iron and has one of the solder suckers , they probably shouldn't try it. They should ship it in for repairs. 

I did bend the leads prior to putting them in the holes so  I could solder one lead and while the solder was liquid pull the cap to the board surface. Then all I had to do is solder in the 2nd lead, do the triming and the super cap was close enough to the board that I didn't need to cushion it against shock that they talk about.

I have my repaired outside on an 2nd temp/humid station and it has made it so far through the winter.

[Weather Spares]

Also to avoid the 3 hand requirement of soldering I find that copper solder braid is a very useful item to soak up solder from a board. It's the equivalent of using kleenex to mop up hot liquid solder.

[SlowModem]

I can see why Radio Shack in this town is rarely full of customers.

Had a similar experience with the RS in my town.  I went in to get a earphone so I could listen to my ipod in one ear and have the other ear to hear the rest of the world.  I asked the teenager if they had one and he looked at me like I was from another planet.  I tried to explain it.  He said they had earbuds, and earbud/microphone things for phones.  But he didn't know what an earphone was.

Geeze Louise!

[Aardvark]

it is a good thing we didn't ask where they kept the potentiometers,  "you know kid, where do keep the pot?"

[ocala]

Fitted the new capacitor yesterday evening and it started transmitting after about an hour in the window this morning.
It still has the depleted battery in for now so will be interesting to see what happens overnight - still on test in the house.

The tricky bit for an inexperienced solderer is clearing old solder from the holes to push the new pins through.
I have a kit with one of those syringe things in to suck it up, but you seem to need three hands to trigger it quick enough 

you are going to need to replace the battery as soon as you are sure the supercap has charged up.   I have a story about the solder sucker bulb.   They are hard to find in town, A city of 350,000 you'd think you would have everything, but sadly no.  So I trot over to Radio Shack and they didn't have one, but one in a mall did, so I drive over there.  I ask for  it and these two teens had no idea , but I spotted it and said I wanted it.   The kid ringing up the ticket asked me what it was, and I explained to him how it was used and he had no idea of what or why to solder something. I explained that, then this other kid looks at me and says " You can also do this"  and he made gestures that you could pick up some powder and spray it into your nose.  I looked at both of them and said " You have no knowledge of what I do for a living, I could be an off duty cop, drug enforcement agent, work for Radio Shack as a corporate spy."   I told them they should never do things that make a reference to drugs or  any illegal.  I paid with cash.  The more I thought of it , the pissed I got. So I wrote the corporate offices and they called back apologizing over and over .  I sheepishly strolled by the store about the same time the next week and the two kids were not at the register, but doing the grunt work and this very cute co-ed was there.  I guess  it helps to do things right. However, I can see why Radio Shack in this town is rarely full of customers.    Thus Endeth The lesson.

Kids will be kids. No point in getting upset.

At least they are working and not out causing trouble. 

[MCDA]

It still has the depleted battery in for now so will be interesting to see what happens overnight - still on test in the house.

How is it behaving for you, now that you replaced the super-cap?

[Aardvark]

it is a good thing we didn't ask where they kept the potentiometers,  "you know kid, where do keep the pot?"

and they don't work there any more.  Probably flippin burgers.

[4wd]

It still has the depleted battery in for now so will be interesting to see what happens overnight - still on test in the house.

How is it behaving for you, now that you replaced the super-cap?

So far as I can tell installing it went OK but did not solve the power drain problem unfortunately.
I just bought a complete new board from http://www.weatherspares.co.uk/ (which came incredibly fast thanks) and it all is back to normal now.
It was just a guess that the supercap was behind the fault - although the symptoms are sometimes like that, seemed worth simply swapping it since it's a fairly easy and inexpensive thing to try replacing.

[MCDA]

I am having the same issues with a VP2.  I dont know why but it just seems to draw more power these days than it was designed to.  I replaced the super-cap with one many times the original capacity and installed a new solar panel.  It was still running out of juice at night so I installed a high capacity AA rechargeable battery.  Works OK but in the winter, when its not getting enough sun, it falls over 

As we have plenty of wind, I have been toying with the idea of installing a very small wind turbine to keep it going over the dull winter months!

[Aardvark]

I am having the same issues with a VP2.  I dont know why but it just seems to draw more power these days than it was designed to.  I replaced the super-cap with one many times the original capacity and installed a new solar panel.  It was still running out of juice at night so I installed a high capacity AA rechargeable battery.  Works OK but in the winter, when its not getting enough sun, it falls over 

As we have plenty of wind, I have been toying with the idea of installing a very small wind turbine to keep it going over the dull winter months!

sometimes the transmitter board also goes bad. I guess for the price, we want it to work forever, and it has its own agenda

[MCDA]

In theory, if a small wind turbine (3-5v, 0-500mA) was connected in parallel with the solar panel, would the on board charge controller handle it?  Has anyone ever tried to power it from alternative sources?   

[4wd]

The normal draw must be quite small, I was surprised how little light the small solar panel needed to start up the TX when I fitted the new main board.
With a faulty component probably in effect drawing current through a short it could be far higher current needed.

[MCDA]

The normal draw must be quite small, I was surprised how little light the small solar panel needed to start up the TX when I fitted the new main board.
With a faulty component probably in effect drawing current through a short it could be far higher current needed.

Yes the Solar panel is actually very small, and a few hours of sunlight is enough to charge the supercap under normal conditions.  Did you test the old board with all the sensors disconnected?  Before you scrap it, you would leave it in a dry place for a few days, then flick the test DIP switch and install a brand new 3v backup battery to see if the LED flashes.  If there is one thing about the VP2 electronics, its seems to be very hardy and built to last!! 

[George Richardson]

I have a few questions that should go under this thread. My understanding is that the Davis VP2 line was analog and is now digital? If I have a VP2 system that is over 5 years old, can I replace the ISS board with a newly purchased replacement without assuring that it is analog?

TIA

George

[johnd]

For about 12 months after it was introduced (in late 2004) the VP2 used an analogue T/H sensor. As long as you have ISS firmware v1.6 you'll be OK with a digital T/H sensor. (See the handwritten number on the little round label on one of the SIM board chips for the F/W revision.)

All ISS circuit boards with v1.6 (or later) firmware can talk to either an analogue or digital T/H.

[George Richardson]

Ok. It sounds as if a new ISS board will work with an old VP2 system. Next step. 4wd, et al, 40 to 50 years ago I would ask no further questions and just go for it, but older and wiser, I recognize my limitations. Would you please give me the removal and replacement steps for the board, paying particular attention to those you think an old f*rt might have trouble with. Oh, this is wireless so it looks to me as if I might need to unsolder the antenna (which could be problematic)?

TIA

George

[Weather Spares]

Hi George,

The VP2 replacement ISS board is normally supplied with the rear case from Davis / its resellers there is no need to remove the old one from your existing case. This is possible without the need to unsolder the antenna though.

Regards
Adrian

[4wd]

You won't have any problem, it comes with the antenna and the back part of the white plastic box all ready to go.
No connections to change other than plugging in the sensors.
The only tricky part is unclipping it from the rain gauge mount.

https://www.youtube.com/watch?v=sCN3cuqaEEc

[George Richardson]

ayde_bury and 4wd,

Thank you so much. Sounds as if even I could do that. Hope I don't have to but I've already had 2 short battery life cycles and I really don't want to send it in for a second "reconditioning" in 3 years.

Thanks again,

George