<span class="highlight">Solar</span> <span class="highlight">Panel</span> advice sought ........

Hi all,
I have recently changed from a 40l Engels unit to an 80l fridge/freezer with a commensurate increase in power consumption ... and am currently revising the layout of my solar panels ..................... to this set-up on my Troopy roof :
Two panels, hinged longitudinally, an 85w and a 120w, both (conveniently) of a similar size.

The 120w panel is 'anderson-plugged' to a 20 amp digital regulator mounted on my overhead console. Works beautifully ..................

The 85w unit,now conjoined to the 120w unit, has it's own FIXED 8 amp regulator (non-digital) ............... previously used as a stand-alone source for my spare (stand-alone also) battery - this regulator unfortunately has been 'liquid-nailed' to the panel itself, alongside the panel terminal box.

(Of course, now I can't get the @#$^*(#?= thing off - without risking damaging the panel membrane.!!

My initial objective was to feed both panel's input (via a double anderson plug set-up) direct to my auxilliary battery.

Because the smaller regulator is 'permanently' fixed to the membrane it has thus also sealed the rear access to the terminals and obviously I cannot disconnect the wiring from this regulator !!!!

QUESTION : Can I now route this smaller panel's output direct to the larger capacity regulator, without risking 'hell and damnation ??'

OR ..............

do I bite the bullet and run a second line from the 85w panel direct to my auxilliary ??

Rather than risking 'headaches, apoplexy and involuntary sphincter release' maybe your words of advice could prevent these possible outcomes ????

Any help would be much appreciated...........

Thanks .............................






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Reply By: Member - John and Val - Thursday, Jun 16, 2011 at 08:40

Thursday, Jun 16, 2011 at 08:40
Pedro,

The ideal solution, as you are obviously aware, would be to disconnect the 85W panel from its on board controller, and connect the panel directly in parallel with the larger panel, then feeding their combined output to the 20A controller.

The next best option, if the controller can't be disconnected, would be to leave it connected , but connect the panel output in parallel with the larger panel's output. Provided you have access to the wires leading from the 85W panel to the controller you should be able to remove enough insulation to make a connection.

If it isn't possible to do this, you can PROBABLY connect the outputs of the two controllers together. Depends on how the controllers operate. This is very much a third best approach. (Connecting the output of the 85W controller to the input of the larger controller will NOT work!)

Other options might include connecting the two controller's outputs together, but adding a high current Schottky diode in the output line from the smaller controller. This will introduce a small voltage drop, hence reduce charging rate, but will prevent it interfering with the other controller.

I think my preferred option, if you can't bypass the 85W controller would be ebay. Sell the present panel and buy one without a controller. Will take a little time, but could be about cash neutral. Your 20A controller should easily handle a second 120W panel in parallel with the first.

HTH

John
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Reply By: Battery Value Pty Ltd - Thursday, Jun 16, 2011 at 09:06

Thursday, Jun 16, 2011 at 09:06
Hi Pedro,

run two wires from your 8A regulator output (BAT+/-) to your 20A regulator output (pos to pos and neg to neg).

OR

bite the bullet and run the 8A output all the way to the battery.

The end result is the same: two regulators with their own panel feeding into a common battery. For option one, voltage drop between the 20A regulator and the battery could build up a bit though, due to the additional current from the 8A reg.
But if this wire pair is 6mm auto wire or larger, everything's fine.

cheers, Peter
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Follow Up By: paulnsw - Thursday, Jun 16, 2011 at 18:30

Thursday, Jun 16, 2011 at 18:30
Perhaps a few lessons in the basics of electricity and charging is well overdue.
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Follow Up By: Battery Value Pty Ltd - Thursday, Jun 16, 2011 at 18:37

Thursday, Jun 16, 2011 at 18:37
Want to stir it up a bit?

Fire away with your concerns, but please be more specific.

cheers, Peter
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Follow Up By: paulnsw - Saturday, Jun 18, 2011 at 13:16

Saturday, Jun 18, 2011 at 13:16
"run two wires from your 8A regulator output (BAT+/-) to your 20A regulator output"
Have you ever physically checked or calculated what happens when you do that? I know you haven't as you would know the result if you had. 1 of the regulators would shut down thinking the battery is charged. In some cases both can shut down. There are a couple of brands of regulator you can parallel but not many, and certainly none of the cheapies effectively.
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Follow Up By: Battery Value Pty Ltd - Saturday, Jun 18, 2011 at 15:30

Saturday, Jun 18, 2011 at 15:30
...I know you haven't as you would know the result of it...

Quite frankly, this is the type of lingo spoken by someone with a pokerface in the hope not to be challenged.

But yes, I know the result from a circuit designer's point of view, confirmed by a real life test result.

FYI, solar regulators never 'shut down' during regulation. They either regulate at float, absorption or equalisation voltage.
If one regulator's voltage setpoint is slightly lower than the other one, it'll just start to reduce the current to the battery a bit earlier, as the battery voltage approaches its setpoint.
This only occurs when the battery is almost fully charged, so there's nothing to be lost in terms of solar energy.

In the test setup, both regulators share the same battery, one supplies 10.7A to it, and the other one 1.7A.

cheers, Peter

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Follow Up By: paulnsw - Saturday, Jun 18, 2011 at 16:12

Saturday, Jun 18, 2011 at 16:12
Try different ones and see what happens. Not 2 identical. Often 2 identical wont work.
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Follow Up By: Battery Value Pty Ltd - Saturday, Jun 18, 2011 at 16:45

Saturday, Jun 18, 2011 at 16:45
sure here we go, two different ones work just as well together.

Seeing is believing.

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Anything else?

cheers, Peter
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Follow Up By: oldtrack123 - Saturday, Jun 18, 2011 at 19:12

Saturday, Jun 18, 2011 at 19:12
Hi Peter

The next thing the young learned one will tell us is you cannot parallel an alternator with a solar panel !!! for the same reasons!!


Peter
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Follow Up By: oldtrack123 - Saturday, Jun 18, 2011 at 19:18

Saturday, Jun 18, 2011 at 19:18
Hi Peter
Correction to above for clarity to the learned one
The next thing the young learned one will tell us is you cannot parallel an alternator output with the solar panel regulator output!!! for the same reasons


Peter
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Follow Up By: oldtrack123 - Saturday, Jun 18, 2011 at 19:43

Saturday, Jun 18, 2011 at 19:43
Hi Paul

Perhaps you can explain this pearl of wisdom from you

Quote" and certainly none of the cheapies effectively""

Why not ??
Each will do it's own thing,&give max available panel output UNTIL one reaches it's set point to change from boost[@ around 14+volts

Peter
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Reply By: paulnsw - Thursday, Jun 16, 2011 at 09:24

Thursday, Jun 16, 2011 at 09:24
"an 85w and a 120w, both (conveniently) of a similar size." if your 120W is the a similar size to the 85W, your 120W will only be 80W if you are luciky. You have been dudded ripped off whatever you like to call it by whoever sold you that solar panel.
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Follow Up By: Member - Pedro the One - Thursday, Jun 16, 2011 at 13:30

Thursday, Jun 16, 2011 at 13:30
Many thanks to John & Val, Peter and Paul - excellent replies and great advice.... !!

Will go with 'paralleling' the two to the auxiliary battery, as suggested.

PAUL : Am attaching a photo of my two panels showing the 85 watt Suntech on the right and the 'alleged 120 watt' on the left. (Ignore the date - unskilled operator !!)

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As is obvious, almost identical in physical dimensions and cell count - but differing in 'cell' layout and size .

No 'properties label' attached to this unit anywhere - but was sold as 120 watts !!!
I was always a bit dubious of it's specifications, based solely on the visual aspect, but was not really aware of how to measure/confirm the specifications.

Can you, or anyone, confirm the ratings from the photo ??

I'm a "NAME & SHAME" person and don't like rip-offs on such these 'luxury home' type products - they still cost us hoi polloi many hard-earned dollars.

Thanks to all ....




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Follow Up By: Peter McG (Member, Melbourne) - Thursday, Jun 16, 2011 at 14:29

Thursday, Jun 16, 2011 at 14:29
Pedro

As you may have picked up there are a few of us that have already been "stung" by what seems to be the same supplier.

I'd do some chekcing with other sellers like Ozplaza that do give size and speciifcations info on listings.

You'll find that an 80 watt panel is around 120cm x 53.5cm.

Cheers

Peter
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Follow Up By: Peter McG (Member, Melbourne) - Thursday, Jun 16, 2011 at 14:29

Thursday, Jun 16, 2011 at 14:29
Pedro

As you may have picked up there are a few of us that have already been "stung" by what seems to be the same supplier.

I'd do some chekcing with other sellers like Ozplaza that do give size and speciifcations info on listings.

You'll find that an 80 watt panel is around 120cm x 53.5cm.

Cheers

Peter
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Follow Up By: Member - Ed C (QLD) - Thursday, Jun 16, 2011 at 15:16

Thursday, Jun 16, 2011 at 15:16
In the "good old days", that seller would have been tarred and feathered... (several times!)

I'm amazed that the market hasn't well and truly woken up to them by now..

And yes, I am one who received under-sized/over-rated/fraudulently labelled panels from these "luxury home" type people ...

In my case, I knew before I opened the package that it was "not as described"..

What angers me is that they continue to rip off unsuspecting folk, as is obviously the case here....

I'll get off the soap-box now ;-))


:)



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Follow Up By: Member - Noldi (WA) - Thursday, Jun 16, 2011 at 16:31

Thursday, Jun 16, 2011 at 16:31
Also stung, not sure if its the same mob, bought mine on evilbay. Again no dimensions provided, was told to read the sticker, which was a computer printed label
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Follow Up By: Member - Pedro the One - Thursday, Jun 16, 2011 at 16:46

Thursday, Jun 16, 2011 at 16:46
Thanks again for the replies :

Further checks confirm the panel size as 1210 x530 (thanks Peter McG) and there is a label clearing stating it is a PMW120wattpanel, and 6.67 amps output.

Cleverly, it was printed on cheap paper and therefore quickly and easily obliterated over time ...... except ............. this one is still quite legible !!

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Have now entered "all hands to Battle Stations" and will pursue that course........

Will first contact them (LUXURY HOME PANELS a.k.a. Solar Energy Store) and see what their response will be.

Will post developements ... as they occur.

Again, thanks to all respondents..............................



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Follow Up By: Member - Pedro the One - Thursday, Jun 16, 2011 at 16:53

Thursday, Jun 16, 2011 at 16:53
ooooops ??? was mistaken about there being no labels - there obviouisly was
and
I stated ......................"and there is a label clearing stating '
should read
"and there is a label clearly stating " .............. !!



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Follow Up By: paulnsw - Thursday, Jun 16, 2011 at 18:29

Thursday, Jun 16, 2011 at 18:29
That panel may be 66W. We have one in our lab and think it comes up as 66W. Does not perform in irradiance less than 92%. We have never tested an unknown brand panel that performs compared to name brand panels. Reason companies like Sharp, Suntech, Kyocera, BP, MKE have got big is because they make quality equipment that performs. I read all the horse manure some type here about their evilBay solar panels, but fact is they don't have the lab equipment we have to test solar panels. If they did they would find out how badly they perform. If you check performance per Watt against price, you will find name brand panels are much better value. I realise you cannot convert the horse manure posters, but hopefully people looking to buy solar panels buy quality name brand panels that perform across the full spectrum.
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Follow Up By: Member - Pedro the One - Thursday, Jun 16, 2011 at 23:43

Thursday, Jun 16, 2011 at 23:43
Paul ..............
Perhaps you might enlighten us as to your area of expertise in this field ??

I note ..... "That panel may be 66W. We have one in our lab" and "We have never tested an unknown brand panel " and "the lab equipment we have to test solar panels. ..."

What leads to the 66W estimate ??

Truly we do not have these facilities, nor the required practical knowledge.
So we can make mistakes .................... but, we can also learn !!

Perchance you may be able to give some 'practical guidelines' HERE ..... to "people looking to buy solar panels " ..... so we can avoid these naughty people ??

Thanks ..... Pedro


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Follow Up By: paulnsw - Saturday, Jun 18, 2011 at 13:13

Saturday, Jun 18, 2011 at 13:13
Pedro you were smart the first time and bought a quality well known brand of solar panel. What made you dive into a cheapie no name brand rubbish with ridiculous claims. Was it what you thought was a great price as in a super bargain and did no homework? Did you not think when you compared the size there was something not right when the 120W panel was near the same size as your Suntech 85W?
When you let the glitter of a supposedly cheap price get in the way of common sense and you let gotta get syndrome set in without research or thinking you are in trouble.
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Reply By: Member - Boeing (PER) - Thursday, Jun 16, 2011 at 18:54

Thursday, Jun 16, 2011 at 18:54
Hi Pedro, You wouldn't have a photo of the digital regulator on the overhead console would you?
I have a troopy with overhead console and am in the process of mounting solar panel on roof racks as well. Would love to see where you have mounted it.


Thank you.
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Follow Up By: Member - Pedro the One - Thursday, Jun 16, 2011 at 23:19

Thursday, Jun 16, 2011 at 23:19
No problem .......

will put one up for you in the morning .



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Follow Up By: Member - Pedro the One - Friday, Jun 17, 2011 at 23:39

Friday, Jun 17, 2011 at 23:39
My apologies, Boeing .... nearly forgot about the pix :


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My wiring is placed under the console, instead of through a hole (much neater) then running via the back of the console, down the LH side pillar and through the firewall direct to the auxiliary battery +/- terminals.

The cabling from the solar panel is through a hole the roof (yep, drilled it meself near the gutter!) and along the ceiling channel and then out the back of the console to the regulator.

As I suffer from OFL Syndrome, I took the easiest route for the wiring but I will eventually do the 'hole thing' - later, as it involves removing the console completely.

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It looks a bit crowded BUT - as it is, it works for me.........

Left to Right : HF speaker, cheap calculator, 60min timer (to keep me awake!) HF handset, solar panel regulator, GME 4400 UHF radio, Codan 9323 HF radio, UHF handset.
The green-handled thingy is a 13" pruning saw, officially for cutting away large trees from my path - unofficially, a personal protection device when needed...!!

The hat is just a hat ....................

(OFL Syndrome is 'officialese-speak' for Old, Fat and Lazy, BTW.)

Hope these help ........ Pedro






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Follow Up By: Member - Pedro the One - Saturday, Jun 18, 2011 at 00:15

Saturday, Jun 18, 2011 at 00:15
And again :

The wiring/connecting process is :

a/Panel terminal box to Anderson Plug, attached to panel frame.

b/ Cabling from the Regulator itself, through the previously-mentioned drilled hole, to another Anderson Plug, close to the hole and permanently fixed to the body, as below !!

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c/ A short Anderson-plugged extension lead, to connect Solar Panel to external Regulator plug !!

Additionally, I have a longer extension lead (9m) which can be hooked up to a 3rd battery, remote from the vehicle, for minor camp electrics ............

As I also have a 3rd (portable folding panel) set-up, in case of need this can be directly connected to the above fixed plug, thus allowing the rooftop panels to be dis-connected or removed completely.

This 'should' complete the exercise ???

And, should the need be, I may be advised alternatively .... ???

Pedro







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Follow Up By: oldtrack123 - Saturday, Jun 18, 2011 at 10:08

Saturday, Jun 18, 2011 at 10:08
Hi Pedro

You may get an idea of the size /type of panel by performing the below non Nata approved tests [Paul if he does reply will not approve]
It will require access the the panel INPUT put to the reg & with the panel surface set @ right angles to BRIGHT sun & not connected to the battery or any other load

[1]check voltage from panel. should be around 20<21

[2]set meter to amps &connect across pos & neg of panel ,for 80watt should get around4.7<4.9amps.

Peter
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Follow Up By: oldtrack123 - Saturday, Jun 18, 2011 at 10:21

Saturday, Jun 18, 2011 at 10:21
Hi Pedro
I cannot edit so a correction to the above

2]set meter to amps &connect across pos & neg of panel ,for 120watt should get around 7.5< 8amps

That co has a reputation of selling panels that are not as represented.

Many of their panels are low voltage panels for use in mains supply systems & are not suitable for battery charging, they may charge but @ a very low rate.

I am yet to work out if they either do not know the difference or if it is an outright con on the unsuspecting users

They do aparrently quickly respond when found out

Peter
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Follow Up By: oldtrack123 - Saturday, Jun 18, 2011 at 10:30

Saturday, Jun 18, 2011 at 10:30
Hi Pedro
I do agree with Paul
If that is a 120watt panel, it denies all the laws of physics & someone has made a magnificent discovery in solar panel technology

Peter
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Follow Up By: Member - Pedro the One - Saturday, Jun 18, 2011 at 11:17

Saturday, Jun 18, 2011 at 11:17
Many thanks, OldTrack ..................

Exactly the type of response I was hoping for ........ gives me a possble way to sort out this problem .

An observation :
I am often apaulled [sic] by the somewhat abrasive and dismissive replies by some people to these type of questions ......... whilst these respondents are often obviously more experienced (and frequently quite knowledgeable,) derogatory references to 'our' lack of knowledge aren't really helpful .... !!!!

Quote:
"If that is a 120watt panel, it denies all the laws of physics & someone has made a magnificent discovery in solar panel technology ."

Very nicely put ............. may I use it in my correspondence ???


Thanks again, Peter .......... Pedro
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Follow Up By: Member - Boeing (PER) - Saturday, Jun 18, 2011 at 14:15

Saturday, Jun 18, 2011 at 14:15
Thanks Pedro for the photo's and explanation. Very much appreciated.
My Troopy was a ex SES S.A. so it has the hole already drilled on the side and a rubber grommet inserted. They would have used it for the wiring for the beacon/s.


Thanks Again

Mark
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Follow Up By: oldtrack123 - Saturday, Jun 18, 2011 at 15:17

Saturday, Jun 18, 2011 at 15:17
Hi Pedro
Happy if I have been of any help
By the way what others have suggested regarding joining the 2nd panel's reg output to the reg output of the 1st panel is ok if the cable size is large enough [to avoid to much voltage drop output] If you can give total length of cable [pos& neg } & cable COPPER diameter can help in that regard too

By all means use that little quote.

RE :"whilst these respondents are often obviously more experienced (and frequently quite knowledgeable,) derogatory references to 'our' lack of knowledge aren't really helpful .... !!!! [end quote]

Often those types do not have the experience or the knowledge they pretend .
Usually shows up when asked to explain exactly why they say so & so, Or why they disagree
There was one a while back on another forum ,also worked in a NATA lab ?? could not or would not answer a single question or attempt to explain !!
WHEN pushed, resorted to
"If you do not understand why should I waste my time trying to explain""

Something along those lines seems to be a common escape route for the type
It has happenned on other forums.
Peter







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Follow Up By: Member - Pedro the One - Saturday, Jun 18, 2011 at 18:07

Saturday, Jun 18, 2011 at 18:07
Peter (Oldtrack) ..............

Hopefully, the end of this now somewhat interesting thread may be at hand !!
I will leave that arena to the 'feisty' one .................

So:
Can I safely run the OUTPUT cabling from EACH panel to a common single Anderson Plug and thusly through to the main Regulator ??
(Having now totally isolated the offending pre-glued regulator )

Points will be awarded for a "YES" answer ......... !!!

Regards ..... Pedro




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Follow Up By: oldtrack123 - Saturday, Jun 18, 2011 at 19:03

Saturday, Jun 18, 2011 at 19:03
Hi Pedro

Yes ,IF
[a]
the panels are the same voltage when open circuit Ie around 20<21 volts

[b]
as long as the cables are large enough [copper dia .] to carry the combined current with out excess voltage drop
[c]
How close [cable length ]to the battery is the MAIN reg ??

Peter
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Follow Up By: Member - John and Val - Saturday, Jun 18, 2011 at 19:32

Saturday, Jun 18, 2011 at 19:32
Pedro - YES - see the first sentence of the first reply to your original post!!! We've got back there after a major detour and some blood letting!

Subject to Peter's (Oldtrack) [a] and [b], YES. Peter's [c] relates to possible losses between controller and battery, but if this hasn't been an issue in the past, will probably not be an issue now.

I don't want to reignite the fire that has now just about burned out, but as a matter of interest, my old 60W (quality) panel is almost exactly the same size as my newer (quality) 85W panel. There have been advances in the past decade, though clearly they don't account for the differences claimed for your panels.

Cheers

John
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Follow Up By: Member - Pedro the One - Saturday, Jun 18, 2011 at 22:14

Saturday, Jun 18, 2011 at 22:14
Thanks, John (and all the Peters/others)

I didn't 'ignore' your initial response (at least, not intentionally !! ...... I just got 'a bit lost' in the ensuing quagmire ......................

I always look forward to your posts/responses as practical and most informative ........ and frequently relevant to me and my Troopy queries !
As I do with many others, of course .

Thusly, my problem has been resolved ......... now for the peripheral engagement with Luxury Homes Products over the fraudulent sale of an incorrectly labelled product ................. they 'owe' me 40 watts !!!!

Will post any responses ................

And, in good faith, thanks to paulnsw for pointing out the mis-representation in the first place.
(I did do my 'due diligence' before buying - but obviously it was of an insufficiency ......... still, it's not a crime, ya know !!)

Thanks again to all ................. Pedro [over and OUT !!]




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