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Author Topic: Battery charging indicators  (Read 2556 times)

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rayd6000

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Battery charging indicators
« on: June 20, 2011, 21:39:09 PM »
Hello;
I have 12 small rolling devices that run off rechargeable batteries and are controlled by inferred remotes. The batteries need to be charged while in the rolling device and when it is time to recharge the batteries the devices roll into a charging station. Under each device is a pair of wipers and they mate with another pair of wipers in the charging stations. At the time of contact the batteries get a trickle charge of 125 milliamps. Allowing the device to move forward 1” the unit comes in contact with a micro switch changing the charge rate to 750 milliamps for 1-Hr then automatically dropping back to 125 milliamps. 

I need a circuit at each charging station that will light a LED’s to show that the wipers have made contact with each other and a second LED to light when the device has move forward to receive the higher charge rate. The circuit needs to be on the charger side of the wipers.
The voltage is 3.5 VDC @ 125 mils and nearly 4 VDC @ 700mils.

I would like the circuit to be part of the charging circuit not just adding extra switches to turn on LED’s when they are bumped. That way if the wipers do not make contact for whatever reason dirty, etc I will know.  I am not using standard NiMH battery chargers.

Thank you.
Ray D.

_pike

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Re: Battery charging indicators
« Reply #1 on: June 20, 2011, 23:23:01 PM »
you should definately provide us a schematic to tell you where to place the led you want to....

rayd6000

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Re: Battery charging indicators
« Reply #2 on: June 24, 2011, 00:28:40 AM »
Hello, I attached 2-different files, PDF & JPG. If you need any additional info please just let me know.
Thank you for your time.
Ray D.

_pike

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Re: Battery charging indicators
« Reply #3 on: June 24, 2011, 02:19:12 AM »
Here is my suggestion.....
1)To the wipers you can use a led in series with a small resistor .What is the voltage accross the wipers?
2)to the micro switch you can use the leg that floats, (most of the micro switches have 3 legs one leg is the common and the other two are the Normally open and normally closed) so hope to have one of them.

rayd6000

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Re: Battery charging indicators
« Reply #4 on: June 24, 2011, 02:48:32 AM »
Hello,
The voltage is 3.5 VDC @ 125 mils and nearly 4 VDC @ 750mils.
Because of the diode in series with the batteries is the reason I can not use a conventional charger.
Yes I do have 3-term on my micro switches and NO is not being used.
By the way the relay and the extra resistor is drawn wrong. I think you know what I mean.
Thanks.
Ray D