Cut off voltage lithium battery?

Rorut said:

This is awesome! I will definitely make and use this one for all projects including lithium batteries. Can't thank you enough for all help and fast feedback spec! And I can admit I'm a bit jealous of all your knowledge
I will try to update my moser list with components above and post it here.

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Rorut said:

Hi again, I have a question regarding my project that I think maybe is related to the circuit. If you look at my image (hope you can understand my drawings) and look where my arrow points between relay 3 and amp.

If I connect ac/dc and turn switch 1 on and then off and measure where arrow is pointing I get around 3v that slowly counts down. I think this is wierd? Shouldn't I get 0v after power off? Is there any current staying that leaks down to the capacitor in the LVC?
Same thing happens if amp is disconnected.

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spec said:

Nothing to worry about:

There is always stray capacitance around that will store electric charge and as your digital multimeter has a very high input impedance it will take a long time to discharge the charge.

The amplifier will certainly have some capacitors across the input lines which will store more charge, but the amplifier circuit will provide a discharge path in addition to the input resistance of the multimeter.

Put a 100K resistor or so across the input to the multimeter and measure again.

spec

PS: Some electronic products, especially hifi amplifiers, have massive capacitors across the supply lines and will continue to operate for a few seconds after the mains power has been switched off.

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spec said:

No probs. Rorut

After looking at your schematic/block diagram, I hope you don't mind me saying this, but I suspect you have three relays too many. Can you post a truth table to show us what you would like to achieve?

spec

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Rorut said:

Thank you. No problem, appreciate it
Only reason I have two of thoose relays is because my switches is small and only handle 1A. Third relay is switching between ac/dc and battery. That is why Im using that third relay.

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spec said:

Work in Progress

(1) Switch two pole, triple throw
https://www.electrokit.com/en/toggle-switch-2p-ononon-solder-lugs.51157

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Rorut said:

That one would probably do it.
AC/DC and charger on one side and battery on other side. And one more switch for on/off charging? (When battery is full the charger beeps loud )

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Rorut said:

Just wanted to share my boombox i have been working on. It sounds great!!

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spec said:

Great work

spec

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