This router ups setup diagram, not an circuit diagram. It’s about a circuit that keeps your WiFi router or Broadband modem always on even in power cuts so that we can use the WiFI.
A 12 V UPS battery is used as backup power source. To charge that, as well as for powering the modem, an 12 Volts power adapter is used here, it should be rating of 1 Ampere to do this job perfectly.
In this router ups circuit, we see adapter is directly connected to battery. As battery is of 12V and gives some 12.5 volts always, we need to step it down to 10V for modem. Find the diagram below.
Working of this Router UPS for modem
Simply here IN4007 diodes are used for forward voltage drop. IN4007 diodes are easy to find and cheap too. It has maximum forward voltage as 1.1V in 25*C. As the modem in this project requires 10V@550ma, the forward voltage comes to 0.55×1.1=0.605Volts. Together 4 diodes reduces voltage by 2.42volts. So 12.5-2.42=10.08Volts is fed to modem which is within 1% tolerance level, so acceptable.
Many modems/routers have an even wider input voltage range, you can directly hookup the 12V battery without any worry to build this ups for router.
TP-Link MR3220 is such a router, it accepts input voltage from about 7v up to 15v happily.
ronin368 says
Hi
in this circuit you're always supplying the modem from the battery , right?
and the battery is constantly charging?
is it efficient?
What about placing a diode between the battery and the adopter so that the battery run the modem in case of black out?
regards
Ebrahim
MOHANRAJ says
Hi bro,
Is it possible to convert the adsl modem to 2g(gsm) modem by some modification in ckt.. If possible means pls give me an explanation with details..
Arup says
No. It's not possible.
Itamar says
Hey Arup,
That's a very good idea i'm considering that instead of buying a UPS for my modem.
I dont understand much in electronics, So if the battery is 10Ah and the input for modem is 500 ~ 850 maH it doesnt effect the modem at all?
(I really dont understand much about Amper)
Is there a way to connect more than 1 modem to this circut and how its done? +battery to +diode and -battery to -modem
and the same in parllel? +battery to +diode2 and -battery to -modem?
Maybe adding a Fuse to this circut to protect from unstable power supply?
Thank you,
Itamar
Arup says
Yeah, add modems in parallel.
Adding a fuse is optional.
No problem at all if you use 10Ah battery or 100Ah.
Gianluca says
Okay a simple power supply ac / dc or need a charger?
Gianluca says
Hi, okay a simple power supply ac / dc?
thanks !!
Fawas says
The battery may overcharge due to continuous charging. Is there any way to limit charging level?
Simon Joseph says
Battery will not overcharge. Once the terminal voltage of the battery attains the voltage of the charging equipment (in this case a 12 V adapter), no further charging will take place.
rinku says
what abt amp? how to reduce amp of battery.
Robert G Holt says
I wants to run my router and swtch both at e time . my router is 5v 1A
and swtch is 5v 2A And My Battery is 6V 4A So
1. What Volt Power Adapter I wants to Connect With it
2. which Kinds Of diod Content Connect With It
Pls Help me