Voltset Multimeters at World Maker Faire

Many tents at World Maker Faire were divided up into booths for companies and various projects. In one of these tents, we found the Voltset booth. [Tom, Ran, and Michael] were on hand to show off their device and answer any questions. Voltset is essentially a multimeter which uses your phone as a display. It connects to an Android phone via USB or an optional Bluetooth module.

Now we’d be a bit worried about the risk of damaging our phones with a voltmeter electrically connected via USB. However, many people have an old phone or retired tablet kicking around these days, which would be perfect for the Voltset. The Bluetooth module alleviates this problem, too – though it doesn’t fix the issue of what happens to the multimeter when someone decides to call.

Voltset isn’t new; both the Voltset team and the similarly specced  Mooshimeter were also at World Maker Faire last year. In the interim, Voltset has had a very successful Kickstarter. The team is accepting pre-orders to be shipped after the Kickstarter backers are sent their rewards.

voltset-2[Tom] told us that the team is currently redesigning their hardware. The next generation prototype board with more protection can be seen in the far right of the top photo. He also mentioned that they’re shooting for 5 digits of accuracy, placing them on par with many bench scopes. We’re skeptical to say the least about 5 digits, but the team is definitely putting their all into this product. We’ll wait until the Kickstarter backers start getting their final devices to see if Voltset is everything it’s cracked up to be.

Measuring 185 µΩ In Circuit

meter

To measure resistance, you usually have to take the resistor to be tested out of the circuit, and sometimes that’s impossible. If you’re using a multimeter, measuring very small resistances is difficult to say the least. Combine both these problems – measuring microOhms in-circuit – and you have a problem that’s perfectly suited for the Mooshimeter.

Announced just a few weeks ago, the Mooshimeter is a two-channel multimeter that communicates with your cell phone over Bluetooth. It’s perfect for measuring current and voltage simultaneously, all while being tucked away in some place that’s either dangerous, inaccessible, or mobile.

The Mooshimeter team put together a great example of what can be done with their meter by measuring the resistance of a car battery grounding strap while behind the steering wheel. To do this, they put alligator clips across the grounding cable and clamped on a current meter.

Inside the car, they whipped out their cell phone and looked at the Mooshimeter’s output for the voltage and current measurement. The Mooshi app has an IV curve (with linear regression in the works), so simply dividing the current and voltage gives them the resistance of the battery’s grounding cable.

It’s a very cool and extremely simple demonstration of how cool the Mooshimeter actually is. Video of the demo below.

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Mooshimeter: The ‘Why Didn’t I Think Of That’ Multimeter

Despite how useful multimeters are, there are a lot of limitations you just don’t think about because they’re the way electronic measurement has always been done. Want to measure voltage and current simultaneously? Better get two meters. Measuring something in a dangerous, inaccessible, or mobile place? You could rig up a camera system to show the meter’s display on a monitor, you know.

Mooshimeter is the better way of doing things. It’s a multichannel multimeter that communicates with your cell phone over a Bluetooth connection. With two channels. the Mooshimeter makes it easy to graph voltage against current to plot a beautiful IV curve on your smart phone. Being a wireless multimeter means you can stick the Mooshi inside a robot and get instantaneous feedback of how hard you’re driving your motors.

Far from being a two-trick pony, the Mooshimeter is actually a pretty good multimeter by itself. It can handle 600V and 10A with 24 bits of resolution. Here are the complete specs. The Mooshimeter is available for preorder here for $100 USD.