Viewing a thread - Davis VP2 Hardware Fault

PRAIRIESCAPES TOURS

RICHARD PAUL RUSSELL LTD

| Search | Statistics | User Listing

Forums | Albums | Quotes | Skins | Language

You are logged in as a guest. ( logon | register )

* MORE LINKS * ARCHIVE FORUMS: OCT 02 - MAY 05 & MAY 05 - MARCH 06

Observations:	Precip, Obs, Synopsis, Obs & Stats, Lightning (Sferics), Satellite, Soundings, SST's, UKww AWS, UK AWS	Orgs:	RMS, TORRO, COL ESTOFEX
Forecasts:	UK Forecast, Wetterzentrale, Westwind, NOAA Plots, PSU Plots, Lightning Wizard, NAO	Tools:	Plotter, Translation, Glossary
Affiliations:	Net-Weather, Storm2K, Abaixo de Zero, Stormlab	UKww:	T & C, Editors, Media, Press Releases

Random quote: Isohel : A line joining places having equal sunshine
- (Added by: Uskys)

Davis VP2 Hardware Fault – SuperCap? Moderators: Forum Managers Jump to page : 1 Now viewing page 1 [20 messages per page]	View previous thread :: View next thread
Speciality Forums and Forecasts -> Hardware Software & Technology	Message format

Stuart Robinson

Posted 10/11/2008 11:30 (#390189)
Subject: Davis VP2 Hardware Fault – SuperCap?

Executive

Location: Mountsorrel, Leicestershire, England

My Soil Temp transmitter has gone down

After a strip down and clean I noticed that the large SuperCap (item indicated by the arrow) has leaked and I assume is no longer working.

Does any now where I can purchase a replacement capacitor? I don’t really want to send it away for such a quick repair.

The SuperCap is a 2.7v 10F (yes 10 farad) electrolyte capacitor – it is a manufactures marking of “Ness Cap”

Maplin don’t stock it.

(IMG_9881.JPG)

Attachments
----------------

IMG_9881.JPG (72KB - 54 downloads)

scanman

Posted 10/11/2008 11:58 (#390207 - in reply to #390189)
Subject: RE: Davis VP2 Hardware Fault – SuperCap?

Location: Avoch, Black Isle, Scotland

Googled it and found this, Stu. Any use?

http://parts.digikey.co.uk/1/1/565506-capacitor-ultra-10f-2-7v-radial-eshsr-0010c0-002r7.html

Stuart Robinson

Posted 10/11/2008 12:02 (#390209 - in reply to #390189)
Subject: Re: Davis VP2 Hardware Fault – SuperCap?

Executive

Location: Mountsorrel, Leicestershire, England

Yea - saw that - but they want £12 for delivery !!!

scanman

Posted 10/11/2008 12:03 (#390210 - in reply to #390209)
Subject: Re: Davis VP2 Hardware Fault – SuperCap?

Location: Avoch, Black Isle, Scotland

Yeah, I saw that too.... for a two quid capacitor?

Mind you, would probably still work out cheaper than having to send it off for repair.

Edited by scanman 10/11/2008 12:04

novice

Posted 10/11/2008 14:56 (#390242 - in reply to #390210)
Subject: Re: Davis VP2 Hardware Fault – SuperCap?

Hi Stuart,
just bought 2 myself, trust me £12 for postage is nothing, before DigiKey opened there UK site it was $69 cheapest option and that's the only place I've found to buy the exact part.. RS do a 2.5v version but I did wonder about replacing it with a rechargeable battery something like this http://www.maplin.co.uk/Module.aspx?ModuleNo=30958

Order a few they tend fail around the 2 year mark (or at least mine have).

Just be careful not to bend the legs to much as I've heard this can decrease the life of the component.

Regards Jon

johnd

Posted 10/11/2008 15:28 (#390246 - in reply to #390242)
Subject: Re: Davis VP2 Hardware Fault – SuperCap?

Location: Ely, Cambridgeshire

Just be careful not to bend the legs to much as I've heard this can decrease the life of the component.

The key thing is not bending the leads too close to the supercap body - this can damage the internal structure of the supercap and lead to premature failure. You need to use eg two pairs of small pliers - one to grip the lead between the bend and the body, which is used to keep this part of the lead straight and prevent any stress being placed on the lead where it enters the body, and a second pair to actually make the bend.

Pete Roberts

Posted 11/11/2008 10:58 (#390464 - in reply to #390189)
Subject: RE: Davis VP2 Hardware Fault – SuperCap?

Location: Runcorn, near Liverpool 2008 Capital of Culture

Stuart Robinson - 10/11/2008 11:30

Does any now where I can purchase a replacement capacitor? I don’t really want to send it away for such a quick repair.

The SuperCap is a 2.7v 10F (yes 10 farad) electrolyte capacitor – it is a manufactures marking of “Ness Cap”

Maplin don’t stock it.

Should you still need one let me know and I'll order one for you with my next wholesale parts order. That way P&P will be just £1 for stamp and Jiffy bag.

Pete

Stuart Robinson

Posted 11/11/2008 11:04 (#390465 - in reply to #390189)
Subject: Re: Davis VP2 Hardware Fault – SuperCap?

Executive

Location: Mountsorrel, Leicestershire, England

Yes I am still searching Pete - I will send you a PM

Stuart Robinson

Posted 11/11/2008 11:07 (#390466 - in reply to #390189)
Subject: Re: Davis VP2 Hardware Fault – SuperCap?

Executive

Location: Mountsorrel, Leicestershire, England

Just to add... that a brand new battery now goes flat overnight in the Leaf / Soil transmitter - so I guess that the Supercap has finally died (short curcuit)

I have turn the unit off...

Pete Roberts

Posted 11/11/2008 12:06 (#390472 - in reply to #390465)
Subject: Re: Davis VP2 Hardware Fault – SuperCap?

Location: Runcorn, near Liverpool 2008 Capital of Culture

Stuart Robinson - 11/11/2008 11:04

Yes I am still searching Pete - I will send you a PM

Caps on order - check your PMs

Edit: You can't directly replace a supercap with rechargeable cells as there is no regulation of charging current needed for a supercap - the capacitor charges with a short but fairly heavy current pulse then just sits there. Should you want to fit a 2.4v NiMH memory backup battery you'd have to add a constant current charging circuit.

Pete

Edited by Pete Roberts 11/11/2008 12:12

novice

Posted 11/11/2008 15:19 (#390515 - in reply to #390472)
Subject: Re: Davis VP2 Hardware Fault – SuperCap?

Pete Roberts - 11/11/2008 17:06

Edit: You can't directly replace a supercap with rechargeable cells as there is no regulation of charging current needed for a supercap - the capacitor charges with a short but fairly heavy current pulse then just sits there. Should you want to fit a 2.4v NiMH memory backup battery you'd have to add a constant current charging circuit.

Pete

Glad I paid my £12 postage just wish I'd ordered more though as a new board is £59....

Regards Jon

Speciality Forums and Forecasts -> Hardware Software & Technology

Jump to page : 1
Now viewing page 1 [20 messages per page]

Jump to forum :

Search this forum
Printer friendly version
E-mail a link to this thread

IJMet

Registered to: UKweatherworld

(Delete all cookies set by this site)

Running MegaBBS ASP Forum Software © 2002-2010 PD9 Software	By accessing UKweatherworld.co.uk you agree to be bound by our Terms and Conditions Unless otherwise stated, all content © 2002-2010 UKweatherworld on behalf of the author. For permission to reuse any content, please email us.