Topic: Good old VP2 console still works but now eats batteries. Any ideas please?

[Ivy Bank]

Hi

I have a venerable Vantage Pro console which I have been using for 18 years. It's still working fine other than in the last couople of months it has started draining the batteries very quickly. The batteries are exhausted in just a couple of weeks whereas they used to last about a year. They really are dead (i.e. it's not a contact problem inside the unit) and I have been using good (Energiser) cells.

I connected the external 5V connector to my lab PSU and it is drawing 10-13mA which is clearly excessive. Does anybody have any experience of a similar problem and have any suggesitons for components which could be causing such a failure? Whilst I realise it is old, I'd quite like to keep it going. And yes, I oculd consider running it from the mains but would prefer to fix it.

Obviously a schematic would be great if anyone has tracked one down. I am an electronics engineer so am confident I oculd fix it.

Many thanks...
Mike

[Mattk]

Does it have a logger installed?

[Ivy Bank]

Nope. I have another console with a WiFilogger in. This old one doesn't. And it was working "normally" until recently and nothing has changed in the way I'm using it.

[NorCal_Dan]

The batteries are exhausted in just a couple of weeks whereas they used to last about a year.

I am surprised the console would run that long on batteries alone.  My guess is the console is staying active for some reason instead of "sleeping" or being inactive when not requesting data from the ISS.  I assume this is not a cabled version of the VP2?  Could it be a wifi issue?  I know the lamps in the console will "eat" batteries if left on.  Without a schematic it's going to be impossible to troubleshoot.

[Ivy Bank]

Yes it's quite normal for them to last > 6 months.
No it's not cabled, lights unused and wifi is not involved / related to this. But thanks

[NorCal_Dan]

https://www.instrumentchoice.com.au/news/davis-vantage-pro-2-frequently-asked-question-guide

Some good info that might provide some troubleshooting help.  I wonder if the reception and polling stats will indicate excessive polling or other anomaly.

[Ivy Bank]

Thanks for the link. This page confirms that the current draw should be 1mA; j am drawing at least ten times this. For the time being I’ve soldered some wires in and connected it to a USB powerbank.
 [ You are not allowed to view attachments ]
Still, I’d love to know what’s gone wrong.

I checked the diagnostics screens and it all looked pretty normal to me.

[NorCal_Dan]

There are sensors onboard the console...temp/hum and barometer. Not sure they would draw that much current, but they could cause side effects.  Example, if the code says to read the barometer every 10 minutes, but for some reason there is no response, it might cause the code to constantly request data leading to more draw on the batteries.

My guess is something on the wireless side of things.  The transmitter has to be the biggest draw so thats where I would start. 

Davis does provide repair services but they ain't cheap.  You could probably source a new console for less than they would charge to fix yours...

[ocala]

There are sensors onboard the console...temp/hum and barometer. Not sure they would draw that much current, but they could cause side effects.  Example, if the code says to read the barometer every 10 minutes, but for some reason there is no response, it might cause the code to constantly request data leading to more draw on the batteries.

My guess is something on the wireless side of things.  The transmitter has to be the biggest draw so thats where I would start. 

Davis does provide repair services but they ain't cheap.  You could probably source a new console for less than they would charge to fix yours...

Could also do a refurb, if they still offer that, but the OP has an electrical background so I'm sure he wants to do it himself.

[johnd]

Sorry, not much help I know but FWIW:

AFAIK there is no schematic publicly available for the 6312 console (or indeed for most Davis parts). And, given that there is no logger or backlight involved, it's a rarely reported issue so minimal community experience to draw on. As per the table in the Davis catalogue, the average draw for a wireless 6312 with no logger or backlight should be around 1mA. So, presumably some component has gone relatively low resistance. But what and where is anyone's guess.

[dupreezd]

I would look for any swollen or burst capacitors as they might often 'short' out drawing excessive current. The two in the picture looks ok, there might be others.

[darcyh]

Is it possible the 'repeater' mode has been enabled? This may increase current draw but unsure as to how much more power this uses.

[johnd]

Is it possible the 'repeater' mode has been enabled?

i’m not aware that repeater on a channel uses any extra power, but having multiple active channels may well do so.

[SnowHiker]

The manual says it can draw up to 30mA, not including the lamps for wireless.  https://cdn.shopify.com/s/files/1/0515/5992/3873/files/07395_234_Manual_VP2_Console_RevZ_web.pdf?v=1656098534

Console Current Draw . . . . . . . . . . . . . . . . . . . . Wireless: 0.9 mA average, 30 mA peak,
                                                                              (add 120 mA for display lamps, add
                                                                              0.125 mA for each optional transmitter
                                                                              station received by console) at 4 to 6
                                                                              VDC
                                                                              Cabled: 10 mA (average), 15 mA (peak)
                                                                              (+80 mA for illuminated display) at 4 to 6
                                                                              VDC

But it only uses 0.125mA for each additional transmitter, so even with eight transmitters that would only be 1mA more.

It makes sense to me that using the Retransmit function (pg 13) would use significantly more power, but I would expect it to be no more than a stand alone wireless repeater, which  claims a draw of 1.5mA ( https://cdn.shopify.com/s/files/1/0515/5992/3873/files/07395-238_IM_7627.pdf pg 38).

So I don't know under what conditions a wireless would draw the stated 30mA (maybe instantaneous draw when retransmitting?), or even 15mA for cabled, other than the lamps, but I would make sure retransmit didn't somehow get enabled as @darcyh suggested.  Maybe blow out the console and make sure dust or other debris isn't shorting something out if you haven't already, or try reseating the ribbon cables or something like that, or whatever you feel comfortable with, especially given your background.

[johnd]

It makes sense to me that using the Retransmit function (pg 13) would use significantly more power,

Yes, I agree. The OP's statement talked about 'repeater mode'. My initial interpretation of this was receiving signal via a repeater, which I suspect would still make a negligible difference to current draw. But yes if Retransmit of the received ISS signal is turned on then this may well cause an increased draw.

[Ivy Bank]

Thanks everyone for taking the time to share your thoughts.
I also wondered about the electrolytics. They both look fine but I didn’t take them out to test. All the others are tantalums.
I haven’t checked if retransmission is enabled - good suggestion. If it is then it must have happened by accident. Is this enabled from the console setup screen?
It would use more current than receive only but not a lot - see how long the ISS lasts on its solar-charged super-capacitor…

[Mattk]

.... I haven’t checked if retransmission is enabled - good suggestion. If it is then it must have happened by accident. Is this enabled from the console setup screen?....

Re-transmit can be activated from the console or from WeatherLinkPC with an installed logger.

[Ivy Bank]

Thanks. I checked but retransmit is off

[NorCal_Dan]

Can you isolate each sensor from the circuit, one at a time, and then RX and TX.  That should narrow down your search.

[Ivy Bank]

Yes, that would make sense. A schematic would definitely help for that

[Mattk]

Not sure what isolating the sensors would do? Only sensor/s in the console are inside temp/humidity & Barometer, main sensors are powered from the ISS so only dealing with data Rx 

[Ivy Bank]

The idea would be to find which part of the circuit is taking excessive current.

[johnd]

Actually, I think a simple first step (if you haven't tried this already) would be to detach the ribbon cable to the display and re-check.