PROFESSIONAL MEASURING AND TEST INSTRUMENTS

OVERVIEW | MULTIMETERS
Testboy digital multimeters offer a wide variety of functions that are designed to simplify daily work routines.
Digital or analogue
Multimeters are equipped with a digital display to provide an accurate, high resolution display. An analogue display returns
an imprecise reading, because the user is required to estimate the values indicated between the scale markings. By contrast
the digital display always indicates the complete measurement value.
Voltage
The principle power supply for electronics devices is 230VAC, which is then converted in so-called power supply units to an
operating voltage for the electronics components (for example computer power supply packs, plug-in mains adapters and
so forth). A multimeter is required to measure these voltages and display the values. The task is made even simpler if the
measuring instrument features autoranging.
Continuity testing
To facilitate testing a good conductive, low resistance connection all multimeters offer a continuity test function with
acoustic signal. The test voltage during the continuity test is so low that it can be guaranteed that only low-resistance connections
are recognised as continuous, and not transistor or diode paths.
Accuracy
The maximum measurement error is detailed by the accuracy of the multimeter. This value is indicated in percent in relation
to the actual measurement value.
Data Hold
Pressing either the "Hold" or the "DATA H" button will freeze the measurement value presently indicated in the display.
This is an extremely useful function if the value has to be documented or it is not possible to read the display at the time
measurements are being taken.
Extract from the EK 1 resolution
Where safety is an issue, components must be used in accordance with their rating data as specified in section 14.1 of the
standard DIN EN 61010-1. A large number of (digital) multimeters on the market are fitted with a fuse approved for 250V
only. The maximum value of measurement ranges for voltage measurements indicated on the multimeters is very often
600V or 1000V; hence, even applying a usual household phase-phase voltage of 400V will exceed the fuse value. Due to the
fuses used in conjunction with insufficient clearance and creepage distances overvoltage events cause dangerous electric
arcing to occur, which represents a fire hazard and can also endanger the health and safety of the user.
23 |