DIY One-Button On/Off Switch for Multimeters
If every time you finish using your multimeter you turn it back to the off position, sometimes you might end up switching it on and off forty or fifty times a day. For example, every time you use the UT890C on the 600V AC voltage setting, you have to turn the dial about a third of a turn to get there, which causes extra wear on the other settings along the way and isn't great for the dial's lifespan. So, is there a way to avoid wearing out the dial? The solution is pretty simple: you can try adding a one-button on/off switch to your multimeter. If you're interested, why not DIY it along with this guide?
You can place the switch on the back cover, hiding it between the slots for the test leads. This way, it's easy to turn the multimeter on or off with just one finger, and the switch won't get pressed accidentally. Once you've decided on the spot, you can drill the hole and trim it to size.
After cutting out a rectangular hole, you can insert a rocker switch. This type of switch can be operated with a single finger, whereas the rotary dial sometimes can't be turned easily with just one finger.
The circuit controlled by the switch simply changes the position of the battery compartment, which can also save you one battery holder.
You'll need to connect wires to the switch and coat the solder joints with some 704 silicone to prevent them from coming loose due to vibration. Otherwise, a wire could fall onto the circuit board and fry a chip, so the details matter.
If you only notice that the position wasn't right after putting the back cover back on, you can trim a little of the protective case to fix it.
And just like that, your one-finger on/off switch is done—instant on, instant off.
If you usually prefer using the manual dial, you can still convert it to one-button on/off as well.
Using the same method, you can modify automatic multimeters, manual multimeters, and clamp meters to have one-button on/off.
For the ZOYI 102, since AC and DC voltages are on the same dial, you just need to press the SEL button to switch between them.
Done.
