Maker Pro
Maker Pro

Old Silicon Chip Magazine project. Solar/Wind controller

AprilSteel

Feb 2, 2017
111
Joined
Feb 2, 2017
Messages
111
I have a few of these kits , that mostly run OK however I have one with a problem which I can't find yet.

It blows the chips .

If I put new chips in it and connect the battery first then the panel everything seems fine.

If I take the battery leads off and put them on another 12 Volt battery there is a spark and it takes the chips with it . I should say chip as its the 4011 chip that goes mostly.

Its called K008E Solar Charger/regulator put out by Oatley Electronics

I've put a circuit below and would appreciate your thoughts on what might be happening.IMG_20170202_152451_BURST005.jpg
 

duke37

Jan 9, 2011
5,364
Joined
Jan 9, 2011
Messages
5,364
I would look at C7/R16. C7 should be discharged in 10 or 20 seconds. If this is not done, then switching on for the second time will put too much voltage on the 4011 input. A high value resistor on the 4011 input would protect it without affecting the operation.

Check that the supply voltages are correct.
 

AprilSteel

Feb 2, 2017
111
Joined
Feb 2, 2017
Messages
111
Thanks . Supply voltages are OK I checked C7 and R16 both OK . While there I added another 1 meg on the input to 4011 . You were right , that had no effect on the 4011operation.

While messing I discovered the 4011 was OK in fact and what had gone was the 5 volt regulator IC2 which is an L4949


Your tractor looks like a massey harris but can't really tell ,the pic is too small . Seems to be alongside and old grey ferggy . I've got two MF 175's and an old petrol/ kero david brown 25C.
Im a bit into old gear myself.
 
Last edited:

shrtrnd

Jan 15, 2010
3,859
Joined
Jan 15, 2010
Messages
3,859
Those CD4011's are early CMOS (Complementary Metal-Oxide Semiconductor) IC's that are very sensitive to static.
If you're continuing to experiment with this circuit, I think Duke37's advice to wait a while for the caps in the circuit
to discharge is a good idea. It doesn't take much to blow the CMOS IC's if they're temporarily over-voltage.
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
Moderator
Jan 21, 2010
25,509
Joined
Jan 21, 2010
Messages
25,509
You could also write to Silicon Chip and ask them. They get enquiries like this and publish them along with their suggestions.

I subscribe to silicon chip, so if you do this and don't have access to the magazine (and they don't reply directly to you) I could pass along their answer.
 

debe

Oct 15, 2011
278
Joined
Oct 15, 2011
Messages
278
That kit is an Oatley Electronics kit & is still available from there as KIT K009D, same circuit. It was designed by OatleSOLAR REG, K009D.JPG y electronics, so I would direct any questions to there not Silicon Chip. If you go to there site & go to that kit, there is a PDF file on how it works. This is a picture of the Kit I built some years ago & still works fine. There is a chance they are not desined to be connected & disconected to a battery with a load creating a spike.
 

AprilSteel

Feb 2, 2017
111
Joined
Feb 2, 2017
Messages
111
Incorporating Duke37's suggestion to increase the input impedance and let the caps sit between connection swaps I put one back into service and it worked fine . Changed batteries with a wait time and it all seemed to go pretty well . Thanks

On the one above its quite a bit different to mine .Whats under the big heatsinks ? I'll have to go read the pdf just to find out now . Thats one thing I don't like about this design - The ins and outs are not marked clearly on the board. When Silicon Chip magazine produced a circuit quite a few followers would produce a kit . It was quite popular then
 
Last edited:

debe

Oct 15, 2011
278
Joined
Oct 15, 2011
Messages
278
The circuit is exacly the same as you posted for the K008E kit. The switching MOSFET & the dual Shotkey diode are surface mounted on the back of the PCB. I fited the heat sink as it quite often has to pass 10Amps & gets quite warm
 

AprilSteel

Feb 2, 2017
111
Joined
Feb 2, 2017
Messages
111
Can anyone tell me how I can add protection to the L4949 chip please? Thats the one that seems to be blowing.
 

debe

Oct 15, 2011
278
Joined
Oct 15, 2011
Messages
278
the max recommended voltage on pin 1 is 28V, so if the battery is disconnected & then reconnected there may be a high voltage spike taking out the IC. There is a 15 to 20V Zenner ZD1. But you could try a 15V Zenner across pin 1 & ground as some extra protection.
 
Top