What is the purpose to use oscilloscopes with a built-in multimeter?
Portable digital multimeter is probably the most widely used measuring device which can be found in every measurement laboratory and which is used by every engineer and technician.
The idea to combine a multimeter and an oscilloscope in one device seems to be very logical. During the debugging and servicing processes for electronic systems on a single board you may need to measure voltage, current, resistance (multimeter functions) as well as to check the waveform and its dynamics (oscilloscope).
Should the oscilloscope with a built-in multimeter be so required therefore? Digital oscilloscope itself is capable of fulfilling some of multimeter functions, namely to measure AC/DC voltage, signal frequency. And if you connect current probes to your oscilloscope it will broaden its functionality. Thus it will be able to measure direct and alternating current.
Firstly oscilloscope ADC is high-speed and 8-bit as a rule. That means the single measurement accuracy won’t exceed 0.4%. Today multimeters use slow ADCs but with high capacity that ensures the accuracy sequence higher. On the other hand the high accuracy is not always required and the capability to measure voltage via oscilloscope ADC can’t be considered useless for combined devices.
Oscilloscope can’t measure resistance like a multimeter. For this purpose it’s necessary to send the test current into the measurement circuits. And oscilloscope input cascades are not able to produce such test current, actually they are not designed to supply from an external power source.
Because of the same reason oscilloscope (unlike multimeter) can’t take the continuity test, measure capacity, inductance or test diodes and transistors (which are ordinary procedures for multimeters).
It’s important to say that multimeter measurement terminals, as a rule, are galvanically isolated from the electricity network (at least due to the battery power supply). Speaking about oscilloscopes only some of them with expensive galvanic isolation of their inputs or those with battery powering have such a feature.
The above examples show that an oscilloscope can’t fully replace a multimeter and combined devices containing oscilloscope and multimeter functions in one housing are demanded by users.
The most convenient device is a portable oscilloscope with a built-in multimeter. Users demand light weighted equipment that may let them save the space in their bags and take such a device into the field. Moreover such devices have batteries.
Today already you have a chance to buy AKTAKOM oscilloscopes of the following configuration:
AKTAKOM ADS-6xxx series digital storage oscilloscopes are a new step forward in the modern oscillography development basing on the most advanced technology and suggesting users unequalled capabilities to solve wide range of measurements tasks at a favorable price.