Tag: Router Backup

It is possible to keep your Wi-Fi on during loadshedding using a power bank, chances are you have one laying around already. This solution won’t be as elegant as using the UltraLan DC to DC Mircro UPS or the Ellies Cube, but it is certainly a good option especially if you have a power bank already and is keen to do some DIY.

Powering your WI-FI (keep your internet on during loadshedding) using a power bank

The concept is simple, you use a DC buck-boost converter (Chopper) to increase the voltage of your power bank from 5V to 9V or 12V depending on what your Router requires. Your mileage may vary.

If you want a simpler solution then this DC UPS is the way to go and if you want to power your laptop then this Laptop Backup solution is a good option.

How to find out the voltage of your router?

Look on the bottom of your Power Supply, there will be a sticker on it showing the Voltage and Amps that you will need to power the router. Take note that the Amp rating on the power supply is often time overstated and the actual router uses much less, this will be important later.

In the example above our Tenda Wi-Fi router has a power supply rated for 12V and 1A, this means we will need to set our boost converter to output 12V.

What is a Buck-Boost Converter & how will it be used?

A buck-boost converter is commonly used to create a constant DC output voltage from a variable DC input voltage source. In simple terms, it allows you to get a higher voltage out than what you are putting in or a lower voltage than what you are putting in.

The one we will be using is a buck and a boost converter, it combines the functions of a buck converter (used for DC voltage step-down) and a boost converter (used for DC voltage step-up).

But you can also use a normal step-up boost converter like the XL6009E1 based module.

• If you are in Cape Town and surrounding area then you can buy one from Netram: Netram boost converter
• If you are in Johannesburg and surrounding areas then you can buy from DIY Electronics: Buck-Boost converter

How to connect the power bank to your router using the boost converter

• You will need a USB cable that you can cut in half, then plug the USB cable into the power bank, and the other end solder it to the boost converter ( actually, solder it first, then plug it in, hehe ).
• Connect a volt meter to the other end of the Boost Converter and then adjust the potentiometer (blue box with screw) until the volt meter shows 12V or however many volts your router requires. The potentiometer has multiple turns. So it may take a while before you have reached the desired voltage. The potentiometer can rotate about 25x from start to finish.
• Connect a wire to the other side of the boost converter and then either to a barrel dc jack or use a wire with one soldered on already. Make sure to connect to the correct positive and negative outputs on the boost converter.
• Plug in your router.
• Bob is now your uncle.

Additional note on buck-boost converters

You can’t beat basic physics. You can’t make energy from nothing. In a steady state, the power (energy per time) out of a converter can’t be more than the power you put in.

Power in this context is current times voltage. In common units, Watts = Volts x Amps. If you put 2A at 5V into a converter, it is getting (2 A) x (5 V) = 10 W in. If it were 100% efficient, that’s what it would put out. If it puts out 12 V, then the current would be (10 W) / (12 V) = 0.83 A.

Of course, there is no such converter that is 100% efficient. The actual efficiency tells you how much of the input power (which is the same as the output power at 100% efficiency) it actually puts out. Let’s say this converter is 85% efficient. That means it puts out (10 W) x (80%) = 8 W, and at 12 V that would be 0.66 A.

This is where that earlier point comes in, the PSU of the Tenda does show 12V 1A, however luckily for us the router rarely pulls 1A and is closer to 0.5A which makes this a potential solution to power your Wi-Fi router, but you will need to do the same for your fiber ONT if you have that. If you have an LTE router then this solution will be fine.

Physics also says you can’t just disappear energy either. So the remaining (10 W) – (8 W) = 8 W has to go somewhere. In the case of a boost converter like this, it goes to heat. The 85% efficient power converter takes 85% of the input power and transfers it to the output, and heats itself up with the remaining 15% of the input power.

Keeping your laptop powered during loadshedding using a power bank

You can use this exact same concept for your laptop, however, you will need a much more powerful power bank as we have seen using the example above, you will need at the very least a 50-watt power bank. We do have some in stock, but I would much rather suggest you buy the WINX 100W Laptop Backup solution, it comes with a cable of your choice that can plug into one of the following brands: Dell, Asus, Acer, HP, and Lenovo laptops.