Solar Panels - Information and Questions

[Simmo]

Hey ChrisM,
Condor is the solar expert on here, hopefully he will pop in?
They do look old eh? Have you got access to a DC clamp meter? The test I use on old panels is the Short Circuit current test.
They could still be showing 18v, but only one string working, so will not give you little or no current.

 

[ChrisM]

Hey ChrisM,
Condor is the solar expert on here, hopefully he will pop in?
They do look old eh? Have you got access to a DC clamp meter? The test I use on old panels is the Short Circuit current test.
They could still be showing 18v, but only one string working, so will not give you little or no current.

Thanks Simmo.
A DC clamp meter / amp meter is one of those things I havent got. I'll ask some people who might know tomorrow.
Suppose youre right when you say it may be ok at 18v but its no good with low amps.
Lol looks like another learning curve coming up :lol:
Cheers

 

[Wally69]

Will this one do the trick ?

 

[shakergt]

I don't know how it is done but find out what wattage they are.

 

[Gem in I]

the surface area of the cells alone look quite minimal chris

 

[shakergt]

I did find some info on them and that is that they are Philips BPX47A (10.7W@25C)

 

[Simmo]

I think they are 47 watts. Popular with Telstra back in the 80's.

 

[Simmo]

Will this one do the trick ?

https://www.prospectingaustralia.co...8022_a2063f1e-c056-4373-a5cb-37266ffafa1a.jpg

Prolly would mate, just move the red lead over to the current socket, put it on 10 amps for a start, and wack it straight across the terminals, with the panel in full sun.
The reason I love my DC clamp so much is you can measure some deadly currents with it!!!
Those panels should only give maybe 4 amps in blistering sun...

 

[Simmo]

I don't know how it is done but find out what wattage they are.

Hey Bud, the Formula is easy. P=IV Where P is Power, I is current and V is voltage.
We dont really want the open circuit voltage of the panel, which could be 18v, so we use the rated voltage of the panel, which is 12v.
Then do a short circuit current test, and that will approximate the wattage.
So short out the red and black wires, with ya clamp meter on and get 2.5 amps in full sun..
P= 2.5 x 12 = 31 watts.

 

[moeee]

I did find some info on them and that is that they are Philips BPX47A (10.7W@25C)

So that would be 10.7 Watts and I figure that would make 'em put out just under an Amp max.

EDIT : and because they are so old , you would be fortunate to get half that.
I won't mention Salvos.

 

[Simmo]

Yeah I saw that when I searched too, but I also found the 47w, which ties in with the model number.
Dunno?!

 

[Gem in I]

Hi ChrisM can I hijack your thread with a question while there are some really helpful members on please mate (I think it's a great topic headline ) :Y:
Q) can I recharge my batteries for everything prospecting related with a cold cranking battery as opposed to the deep cycle and if so would a fuse need to be installed as safeguard.
Basically I don't want to through out my new truck battery, can it be utilized with solar panels.

 

[ChrisM]

Thanks for all the replies guys. Much appreciated.
I'll try and work out the amps this weekend and pass a judgment on the output then.
Im wondering though, lets assume they pump out 2.5amps. I would guess that is the combined output of both panels [correct?]
The size of each panel is aprox 450 Wide x 350 Long. What do "modern" panels of that size pump out? and if needed is it possible to
get panels of the exact size to fit into the existing housing?
As "Gem in I" stated "the surface area of the cells alone look quite minimal" does that make them redundant in todays technology?
Thanks again for the input
Cheers
ChrisM

 

[moeee]

Basically I don't want to through out my new truck battery

I do not understand your post.
Are you considering throwing out a NEW truck battery ?

 

[Simmo]

Thanks for all the replies guys. Much appreciated.
I'll try and work out the amps this weekend and pass a judgment on the output then.
Im wondering though, lets assume they pump out 2.5amps. I would guess that is the combined output of both panels [correct?]
The size of each panel is aprox 450 Wide x 350 Long. What do "modern" panels of that size pump out? and if needed is it possible to
get panels of the exact size to fit into the existing housing?
As "Gem in I" stated "the surface area of the cells alone look quite minimal" does that make them redundant in todays technology?
Thanks again for the input
Cheers
ChrisM

Technology has moved on leaps and bound mate, that is why the prices have plummeted...
I suggest looking on fleabay and seeing if you can find something to fit???
https://www.ebay.com.au/itm/12v-100...m=391496125478&_trksid=p2047675.c100005.m1851

 

[moeee]

The size of each panel is aprox 450 Wide x 350 Long. What do "modern" panels of that size pump out?
ChrisM

I'm not so sure that modern panels pump out considerably more.
The benefit has been more in the lower cost , a bit like them flat screen TV's have dropped tenfold in price in the last 10 years or so
Same story with solar panels

 

[Gem in I]

Well yes moee if it doesn,t have a practical use with solar panels other than just being able to be charged it can go to simms metal with the truck. My only knowledge with recharging sdc batteries/zed/lights/uhf and soon hand held gps has been with a deep cycle battery which I know is safe recharging for these items but I know the ccb has a higher out put initially so was wondering if this would I suppose blow crap up if without a fuse /breaker.
Sorry about the layman terms but would really appreciate a laymans response with no disrespect intended.

 

[Simmo]

Hi ChrisM can I hijack your thread with a question while there are some really helpful members on please mate (I think it's a great topic headline ) :Y:
Q) can I recharge my batteries for everything prospecting related with a cold cranking battery as opposed to the deep cycle and if so would a fuse need to be installed as safeguard.
Basically I don't want to through out my new truck battery, can it be utilized with solar panels.

I wish Condor would chime in, but I'll try my best??

A deep cycle battery is designed to have constant, drawn out discharges, then charge cycles... they dont like a massive current draw in a short period.
So ideal for a fridge, or running a camp site TV and lighting etc over night.

A crank battery can supply a whole fistfull of current at a time... a relatively short time.. (you can do small welding repairs with yer car battery..) It charges fast, with perhaps a 60 or 80 amp alternator when the car is running...

So to answer your question, charging detector batteries and the like on the crank battery will not ordinarliy cause any dramas. (Not running an inverter tho!).
If you are using the 12v chargers supplied, they are fused, so no more need, normally. (if you are running a power lead from the crank battery, to say the back of the vehicle, yes, that lead needs to be fused AT THE BATTERY!!!)

 

[Gem in I]

Top stuff simo cheers inverters will probably be a question further down the track and chris m whether it's feasible or not about the panels at least you will learn more from the journey :Y:

 

[Simmo]

Well yes moee if it doesn,t have a practical use with solar panels other than just being able to be charged it can go to simms metal with the truck. My only knowledge with recharging sdc batteries/zed/lights/uhf and soon hand held gps has been with a deep cycle battery which I know is safe recharging for these items but I know the ccb has a higher out put initially so was wondering if this would I suppose blow crap up if without a fuse /breaker.
Sorry about the layman terms but would really appreciate a laymans response with no disrespect intended.

Hey no worries Bud!! I just hope that my info is up to ConDor's standards!!! He is a pretty thorough bugger!!!

OK, you typed, whilst I was doin' my bit.

The batteries dont 'put out' more than each other... They are 12volt. Thats it.
The high CCA crank battery, as I mentioned, you can weld with....big amps quickly. (to be frank, you could do that with a deep cycle battery, but you would need to go buy a new one fairly soon...)
A fuse, or breaker, will not stop any higher voltage going to what ever is connected to it.....
A fuse, or breaker, could stop a fire in the vehicle, if installed correctly, and something goes wrong with the connected device.

I think where your info is coming from is that a crank battery, is charged by an alternator, which has a fairly rudimentary regulator....
It is the regulator that stops the over voltage that I think you are getting at, that can kill older electronics...
These days, cars run lots of electronics, some, have their own regulators, so the power coming in, doesn't really matter. They can handle it!

Your chargers, I bet are SWP or switch mode power supply charged, and voltage differances wont matter.

Grab a fairly new 240 v device at home, look at the compliance lable underneath... it prolly says it can take an input voltage of 90-250 vac!!!
Thats switch mode power supplies for ya!