I am trying to make a battery backup for my home alarm system using a 5V power bank.
My alarm system brain uses a maximum of 5V 1A. I have a 10,000Mah power bank that both gives and takes 2 amps, a 2.5 amp charger, and a high quality 2.1A capable USB cable.
If I connect the alarm to it's wall power adapter it works, which is no surprise.
If I connect the alarm to the power bank alone, the alarm works off of the power bank.
If I then plug the charger into the power bank it starts charging and the alarm keeps working.
If I kill power to the charger with an X10 there's a split second power drop and the alarm reboots.
The power drop is not enough to see from the alarm's indicator light, it just turns red and reboots. If I hook a voltmeter with battery tester LED's to the wires I can see the blip in the output when wall power is cut.
It takes about 60 seconds for the alarm to reboot and re-arm... ok in a power outage, but too much time if bad guy is the one who cut power before breaking in.
I tried adding a small, big, and giant capacitors in parallel on the cable between the power bank and the alarm.
The alarm works with a 470, 1k and 2.2k uf capacitor, but still reboots.
The alarm lights up but will not boot and flickers with any change with a 12k uf.
I am ready to abandon capacitors as an option, but figured I'd ask first.
Can this even work with just a capacitor or do I need to look at other more complicated circuits?
My alarm system brain uses a maximum of 5V 1A. I have a 10,000Mah power bank that both gives and takes 2 amps, a 2.5 amp charger, and a high quality 2.1A capable USB cable.
If I connect the alarm to it's wall power adapter it works, which is no surprise.
If I connect the alarm to the power bank alone, the alarm works off of the power bank.
If I then plug the charger into the power bank it starts charging and the alarm keeps working.
If I kill power to the charger with an X10 there's a split second power drop and the alarm reboots.
The power drop is not enough to see from the alarm's indicator light, it just turns red and reboots. If I hook a voltmeter with battery tester LED's to the wires I can see the blip in the output when wall power is cut.
It takes about 60 seconds for the alarm to reboot and re-arm... ok in a power outage, but too much time if bad guy is the one who cut power before breaking in.
I tried adding a small, big, and giant capacitors in parallel on the cable between the power bank and the alarm.
The alarm works with a 470, 1k and 2.2k uf capacitor, but still reboots.
The alarm lights up but will not boot and flickers with any change with a 12k uf.
I am ready to abandon capacitors as an option, but figured I'd ask first.
Can this even work with just a capacitor or do I need to look at other more complicated circuits?
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