Archive for Smart Tweezers Tricks and Tips

Digital Multimeter Smart Tweezers does not measure

// January 5th, 2011 // No Comments » // Smart Tweezers Tricks and Tips

There are two  most likely reasons why Digital Multimeter Smart Tweezers does not measure:

  1. The front-end circuit is burned. This happens if you apply voltage higher than allowable (1.4 Volts in Auto mode and 8 Volts in Voltage mode) or try to measure a charged capacitor with Smart Tweezers. Obviously Smart Tweezers require repair in this case.
  2. The slide-switch at the bottom-left corner of Smart Tweezers is in wrong (right-most) position. In this case the problem is easily fixable by sliding the switch into the right (left-most) position.

Measuring Small Inductances with Digital Multimeter Smart Tweezers

// September 3rd, 2010 // No Comments » // Smart Tweezers Tricks and Tips

Smart Tweezers are capable of measuring inductances as small as 1 micro Henry with accuracy of about 5%. However, it should be kept in mind that Automatic mode is not suitable for this type of measurements and gives results roughly 10% lower than actual values.  Setting the Test Frequency to 10 KHz resolves the problem. Another thing has to be noted: inductive components are designed for a use at specific frequency and this frequency is shown in the component datasheet. Very often this frequency is much higher than that used by Digital Multimeter Smart Tweezers and therefore values measured at 0.1, 1 and 10 KHz may significantly differ from the nominal value of the component.

Parasitic probe capacitance of Smart Tweezers

// August 25th, 2010 // No Comments » // Smart Tweezers Tricks and Tips

How to extract parasitic probe capacitance of Smart Tweezers?

The parasitic probe capacitance depends on the distance between the tips, that is it will be different for different measured component sizes. To obtain the value of capacitance of the Smart Tweezers probes of you have to do following:

a) Select mode for capacitance measurements by setting MEASURE -> MODE -> CAP. Letter C will indicate that you selected capacitance measurement mode.

b) Select measurement frequency 10 kHz by setting MEASURE -> FREQ -> 10 kHz

c) When you squeeze the probes until the size of the gap is equal to the size of component which you are going to measure the parasitic capacitance value will be displayed on the screen. This is the value that you have to subtract from any measured capacitance of the same size. Typical parasitic probe capacitance is about 1.5 pF.