Wesley's Tool-Box

Nearly a decade ago, you would have seen me wearing all sorts of gadgets around my waist, as evidenced by this television broadcast. The problem with this was clearly illustrated in that video - it takes a bit of time to put them all on the belt, however useful they may be.

I haven't let go of the carry-them-all attitude, but things have worked in my favour. A lot of the gadgets I had to carry separately were now integrated into a single device (smartphone). That meant less stuff to carry, and I was able to reduce the number of pouches and bags on the belt over the years. I ended up with a phone and an external battery each in a holster, and a bag that held adapters, cables, and other miscellany.


But then large iPhones came along. When I put it on my belt, it occupied a sizable area of my waist. This got me thinking: since the phone is thin enough, maybe I could put it in a belt bag that can store other stuff with it. And this is how I now just have this one bag hanging from my waist.

As you can see here, my iPhone 6S Plus and the slim external battery fit nicely into the front pockets of the bag. They're accessible by opening up the flap usually held in place with a hook-and-loop fastener. I also have a paper clip there in case I need to change the SIM card or poke a reset button.

Of course, there's a lot more hiding behind. Let's take a look at the rear compartment.

A few months ago, I noticed that the first generation FLIR One thermal imaging module for iPhone 5 & 5S went on a bargain sale online for about US$110. Since the newer version and the competing products were two to three times more expensive I thought it would be a great chance to own a thermal imaging camera of my own and ordered one. Good thing I did, because as of this writing the price went back up so high that you'd be better off getting the newer version.

Mine arrived after a couple of weeks and I was already impressed with the nifty packaging. The product itself was also well-built and tightly integrated with my iPhone 5 once I put it into the provided case. Functionally, it works pretty much as advertised. You can see the thermal images of your environment through the phone's screen, with objects' contours enhanced using the images from a regular camera next to the thermal one. This technique, called MSX, is a way of mitigating a relatively low pixel count of the sensor (80 x 60 = 4,800). You have to recalibrate the sensor from time to time using a sliding switch next to it, which is slightly inconvenient at times.


Other device specifications limit the use of this module mostly to indoor use. The maximum range is about 30m (100 feet) and can only detect between 0°C to 100°C (32°F - 212°F). It does work quite well if you work within these limits, though. I can see where the heat leaks in my house and whether the floor heating is working properly, to give some examples.

To me, the fact that it works only with iPhone 5 or 5S out of the box was its biggest disadvantage because the larger iPhone 6 and 6 Plus series came out just two months after its official availability. FLIR did address this problem by releasing a second generation model a year later that solved the form factor problem (just plugs into the bottom of a phone) along with an upgraded pixel count (160 x 120 = 19,200) and range (-20°C to 120°C). It also does auto-calibration, boosting its convenience. But what about for those who already own one and upgraded to the newer iPhones?

You could use it on a spare iPhone, like I initially did, or modify it. There are aftermarket phone cases to fit an iPhone 6(S) or 6(S) Plus. But these require you to cut off the curved area to the side of the connector on the module so that they won't interfere with the wider width of these phones. Otherwise, the Lightning connector wouldn't go all the way in. But I did not like to mutilate it like this and decided to find another way.

As the hunt for even more potential waste of power continued, I brought in the help of thermal imaging technology. By scanning each place with a thermographic camera attached to an iPhone (FLIR One; I'll write about this later) I can find any hot or cold spots that seem to be out of place.

One of such "hot" spots I found was on the side of an air conditioning unit. It wasn't being used, but standby power drawn from the wall outlet was slightly heating up the control circuit and was readily visible via thermal images. I could just pull the plug until summer, but I decided to take a step further.


I replaced the default wall outlet with the one that had an integrated switch. This way, I could cut the power from the outlet with a switch when the air conditioner isn't in use, instead of having to pull the plug. Not only would this be simple to operate, it would avoid the mechanical wear. I should have done this ages ago.

As part of my ongoing data collection, I then tried to measure how much power the air conditioners in the house would consume while trying to cool the house. Sadly, the rooms were not hot enough for them to start cooling the air. I'll have to check them out again when summer comes.

As it is the case with the houses these days, there are lots of electronic devices littered throughout my home, plugged into wall outlets and USB ports. Measuring how much power these consume in their active and idle states would provide a good starting point in how to cut off unnecessary use of electricity. So that's exactly what I did over several days, and the results from the living room and computer/network equipment are now in. I'll be looking at other appliances as chances allow later on.

I tabulated the full results at the end of this post. But first, I'll talk about some interesting observations worth mentioning.

1. Beware of Light-Embedded Switches on the Power Strips

The lights on the switches of the power strips consume as much power as the devices capable of efficient standby - about 0.2 to 0.25W. This seems excessive for an LED, so I did a bit of searching. It turns out that most of these switches use neon lamps because the operating voltage is around 90V, making it relatively easy to integrate into 220V power using a simple resistor. With a nominal operating current of 1mA, the whole neon lamp + resistor assembly would consume 0.22W = 220V x 1mA.

LEDs, on the other hand, operate around 2 to 3V at 15 to 20mA, being about twice as efficient (neon: 90V x 1mA = 90mW, LED: 3V x 15mA = 45mW). But if you use a resistor to meet the voltage requirement, it would end up wasting much more energy (neon: 130V x 1mA = 130mW, LED: 217V x 15mA = 3,255mW). So you need a power converter instead, but they are neither as cheap or small as a tiny resistor. It's easy to see why neon lamps won out.

If your goal is to waste as little as possible, you would need to avoid having these lights on all the time. If six of these switches are always on, it would equate to about 1.3W, or about 1kWh per month of wasted energy. This is something to keep in mind when choosing a power strip for use in a room. If most of the stuff are used all the time or the standby power is low, it would be better to use a simpler power strip.


2. Fully Charged Devices Still Leech Power

There are lots of handheld devices out there, and many of them are conveniently charged when placed on a dock. The problem is that even when the device is finished charging, the charging circuit still draws some power to keep the battery topped off.

For one thing, my electric shaver was found to be sitting idle and sipping nearly 1W for several hours even after being fully charged. Considering that it only takes a few minutes at most to get back to full after a shaving session, this seems to be an unneeded waste. I've changed my usage pattern so that I charge the shaver once every other week or so, and cut the power to the charger once I see that it's done its job.

Then there's the Motoroi smartphone that I've been keeping around its vertical dock as a desktop clock for about five years ever since it was no longer my main phone. The measurement showed that, even though it's kept fully charged, it was drawing about 1.2W from the USB hub all the time because the screen was always on. Like the power strip lights, this is enough to affect the last digit of my monthly electricity usage. So I decided to retire the old phone and replace it with a normal digital clock.

Similar to what was going on with Motoroi and the shaver, smartphones plugged into the dock were also found to sip a bit of power after a full charge. Unplugging it after charging seems to be the "smart" thing to do.

The smart meter I installed last month is running nicely, but using it to measure a precise power consumption of an individual appliance is cumbersome as you need to have everything else stable. So it was time for me to invest in a plug-in type electricity monitor. After some comparing, the one from by the company that made the smart meter was deemed most practical. Named SJPM-C16, it cost me about US$18.50 (KRW 22,400) after discounts.

The goal of this sort of electricity monitor is not just about informing you of electricity usage, but also getting you some ideas on how to make savings from such info. Considering this, I liked the way it was packaged. It was pretty compact and minimal, with hardly any waste of space or materials.


Even the manual is a neatly-folded single sheet of paper that lists everything that you need to know when using the product. This includes the fact that South Korea has a bizarre 6-tier exponential residential pricing for the retail electricity, and that this monitor fully accounts for this when calculating the costs. You can also configure for other pricing schemes and the tier prices themselves are also adjustable, making it useful even if there are future changes.

Now armed with this capable tool, I set out to check the power consumption of every appliances and devices scattered throughout the house.