How to avoid short circuits: Use a multimeter to measure the voltage of each line on a printed circuit board.
Multimeter measurement of any circuit electronic components, in your pen did not touch the electronic circuit components before, must first check the status of the multimeter, such as you measure the DC voltage, be sure to hit the DC voltage gear, if you do not know the circuit voltage is how big, the first is to hit the gear to the highest gear. If you are measuring AC voltage, you must hit the relevant AC gear, if you do not know the size of the voltage, but also the same first hit the highest gear to measure. After measuring the data in the highest position, adjust the position according to the need to carry out accurate measurement. Remind everyone to check the status of the multimeter is to prevent some people will be in the multimeter is resistance or capacitance file directly to measure the voltage, which will cause a short circuit burned things possible. So before measuring anything, we must develop a number of habits is to be sure to look at the status of the multimeter's gear, confirmed as no error before measurement.
First of all, to answer the question of the subject: how to avoid short-circuit multimeter to measure the voltage of the circuit board on the line
1, as sharp as possible multimeter tip
In my reading is still in school, I followed my brother's a habit, that is, I like to bar all their multimeter pen metal front end are polished very sharp, sharp multimeter tip, can be as small as possible to contact the circuit board area, for some small areas of patch component measurement can prevent the tip of the pen is too thick resulting in the accidental touching of the adjacent contacts. This way if you are afraid of the polished meter pen is easy to oxidise.
2, find a spare black pen, the black pen transformed into a crocodile clip
Find a pair of extra pens, the black pen, the end of the hand holding the pen, cut, find a crocodile clip to weld on, spare. Of course, if you do not want to do it yourself, then you can buy ready-made, red and black pens have.
Measure the voltage of the circuit board, first judge the part of the circuit board to be measured is the DC voltage or AC voltage, if it is DC voltage, first of all, the multimeter's gear settings, hit the DC voltage measurement gear, and then a hand to take the black pen in one hand to take the red pen, the black pen are grounded, as close as possible to find easy to put in contact with the grounding point, the general grounding point of the circuit board are relatively large. Red pen and then separate to measure the circuit that needs to be measured. At this time, the more sharply polished multimeter tip, measuring some of the fine patch components circuit, the more convenient. If the two hands are not convenient to take the pen separately, this time we said earlier, the production of spare with alligator clips of the pen at this time can come in handy, the black pen with alligator clips connected to the alligator clips to the circuit board on the ground, the red pen can be measured at will the entire DC circuit.
If you encounter a particularly thin circuit, and there is no sharp enough pen tip, you can find a sewing needle, with no insulation of thin copper wire to sewing needle winding fixed in the pen tip of the pen, so that can also be measured.
