Single universal measurement device that can be used to measure voltage [V] and current [A] in both AC and DC, as well as resistance [Ω]. Often many other ranges are available like frequency [Hz], duty cycle [%], capacity [F], ... Most are hand held, some more expensive ones come as a bench model.
3
votes
4answers
350 views
why is wall voltage measuring 175V?
I was trying to use a DM-4100A multimeter to verify a power supply, and I'm not sure I'm using the multimeter correctly. The multimeter is >10 years old too, so maybe it is not working correctly.
...
3
votes
1answer
76 views
What do I need to know about leakage current?
I recently suggested a plan of removing one end of a resistor from a breadboard to remove it from the circuit in order to measure its resistance, but my mentor suggested that this won't work for high ...
-2
votes
0answers
71 views
How to stabilize the value of ADC in PIC microcontroller? [closed]
I have been designing auto range multimeter using PIC microcontroller. Having problem in the auto range switching due to the ADC reading since ADC reading for particular voltage varies by 100 to 150 ...
0
votes
1answer
79 views
How does a multimeter convert voltage/current to a numerical value?
Just wondering... How does a digital multimeter work ? How can it convert a voltage, a current or a resistance to a numerical value ? I guess there is some programmable chip inside, but how does this ...
0
votes
1answer
49 views
range switching problem in auto range multimeter using PIC microcontroller
I am designing a auto range multimeter with PIC microcontroller and added extra circuitry for attenuating the signal uu to 3.3V for ADC of PIC controller. The problem I am having is in the auto range ...
5
votes
3answers
404 views
Can I burn components / short circuit by using a multimeter
It's probably not new to you, but sometimes we want to analyze a powered circuit with a multimeter. I love to do that, but I'm a little worried that I might burn some components or the whole circuit.
...
1
vote
1answer
92 views
What tests for a defective IC may be done with only a multimeter?
Linked to an earlier post How do I test a circuit without an oscilloscope?
Background :
Inching forward from the previous post I started to do a simple 555 astable with super super long duration ...
2
votes
0answers
95 views
Hard-disk write/read head electronics
This is a sensor arm of a hard disk containing a GMR or TMR magnetic sensor and a coil for creating the write field (1-3 GHz at around 2 Tesla as far as I know).
I'm counting 6 conduction lines, ...
3
votes
7answers
227 views
What is the easiest way to connect a breadboard to a multimeter?
The test leads on my multimeter are too large to fit in the holes in my breadboard. How can I easily connect my multimeter to test voltage on my breadboard?
2
votes
2answers
77 views
What is the best way to switch between different ranges when designing a multimeter using microcontroller?
We are developing a multimeter using a PIC18 microcontroller and we are searching for the best method to switch between different ranges in multimeter with the smallest possible amount of switching ...
5
votes
2answers
228 views
How to adapt a 100 mA DC ampermeter to measure up to 5A?
I have a DAS(Data acquisition system) that can measure DC (up to 30V) and I want to know what is the power a device is consuming, the current measurement available for that DAS is in the range ...
2
votes
1answer
172 views
Why does my PSU die everytime I test with multimeter
I've set up my PSU to use as a "lab power supply", I'm trying to obtain 12 Volts at 14 amps. I have the red, orange, yellow, black wires separated, and connected the green wire to ground to keep the ...
1
vote
3answers
147 views
How much Ampere is displayed on the multimeter?
here is a picture of a multimeter:
the display shows: 02,0
is it 2A or 2mA ?
1
vote
2answers
201 views
Inexpensive multimeter for integrated current measurement
I'm building a simple circuit with an Arduino Nano board, which will read signals from a Hall sensor and periodically send pulses to a small 5V solenoid. I'll drive it from 6xAA batteries in series, ...
7
votes
2answers
195 views
Where to leave the test leads on a Fluke multimeter
I think this is somewhat of a "trade secret".
Being a software engineer for embedded devices myself, I often find myself using oscilloscopes and multimeters. I have always wondered about my Fluke ...
-5
votes
2answers
114 views
when the resistor is high, is the output voltage low or high? [closed]
I am investigating potential/voltage divider circuits. I have read alot about voltage and resistance but am confused on one thing. When the resistor being tested by the voltmeter is high ohms is the ...
2
votes
1answer
114 views
Measuring amperes, what the reading mean?
I am new to electronics, but I don't know what the readings mean. I took measurements with a digital multimeter, the power source is a 9V battery and I have a load a LED.
...
1
vote
1answer
98 views
DMM and Power Supply
If I connect a digital multimeter directly to a DC power supply, the voltage shown on DMM is higher on the power supply.
For example, if the source is 3.29 V then DMM shows 3.31 V. What is the reason ...
2
votes
2answers
179 views
Using a multimeter to measure the current of a microprocessor
OK. I'm pretty sure my inexperience is going to show here. I had the task of finding out how much current a microprocessor was drawing. I was going to measure, with a multimeter, between the point ...
3
votes
1answer
122 views
What is the practical benefit from very sharp probe tip and fast continuity test of DMM?
What is the practical benefit from very sharp probe tip and fast continuity test of multimeter?
I was searching for a while with google and in ee.se but results contain mainly a dmm seling ads with ...
2
votes
1answer
511 views
How to check if my multimeter's fuse is damaged?
I recently bought a cheap multimeter. I played around measuring stuff on simple circuits and I think I managed to damage it as I don't seem to be able to measure current anymore (always get zero ...
3
votes
2answers
385 views
Why does a multimeter show VAC on VDC power supply output?
I used my simple digital multimeter to measure the real output of several small PSU's I have got at home. They all should give just direct current and show some values in VDC mode, but the multimeter ...
3
votes
4answers
238 views
Checking maximum current provided by charger, how?
Using only an entry-level multimeter (and an assortment of common discrete PTH components, say on a breadboard), what could be a reliable way to check the maximum current that a switched-mode AC-DC ...
1
vote
3answers
194 views
Multimeter ranges
I am a software developer trying to understand how computers work at a lower level.
I have purchased a digital MultiMeter. I realise that MultiMeters enable you to measure voltages, ohms, amps etc. ...
1
vote
1answer
62 views
How do I troubleshoot a broken SAA3004 Remote control transmitter used in a remote control?
I'd like to troubleshoot and fix a broken remote control for a Guldmann ceiling lift that uses the SAA3004 remote control transmitter (documentation below in link). Can someone explain the tools ...
2
votes
1answer
427 views
How to determine the units when reading a multimeter?
Say for instance I am trying to measure the current. The units around the edge of the multimeter is 2000u, 200m, 20m, 10A, etc.
Does this mean that the reading displayed on the multimeter is in that ...
0
votes
2answers
139 views
In Digital Multimeter note accuracy in digits
I have digital Multimeter noted in the multimeter accurcy is range 0 - 1000v at 0.2% +30 digits in this range what is 30 digits?
1
vote
1answer
176 views
How do I choose the right replacement fuse for my multimeter?
I have a BK Precision 2709B Multimeter. I managed to blow the uA fuse (500mA/500V fast blow ceramic) on it. Is it an ok to replace this fuse with a 500mA/1kV fast blow ceramic fuse? What impact would ...
2
votes
1answer
174 views
Current/Voltage measuring using Ammeter/Votmeter
I have to measure current/voltage of an unknown circuit. So why should I start with the highest rating and gradually come to a smaller value to identify the current/voltage? What's wrong if I start ...
-1
votes
2answers
252 views
circuit for multimeter without a ic or a timer like ic741 or 555 timer
hey i need to make a multi meter on a bread board without ic or timers. which measures current, voltage, resistance and also inductance . can any show me a circuit which will work . i tried some but ...
6
votes
2answers
387 views
Is a large hFE value a sign of damage?
I have been testing a couple of BFY50 transistors that I salvaged using my multimeter. One of them reports an hFE of ~109 (this looks consistent with the data sheet value of 112). The multimeter ...
1
vote
1answer
177 views
Where can I find DMM probe sockets?
I am working on a DMM project and need sockets for standard probes. I don't even know what keywords to search for these. I could fallback and use banana sockets but it would be better if I could use ...
7
votes
6answers
397 views
What to look for in a multimeter?
When selecting a multimeter, what should one look for in terms of safety features and measurement capabilities?
What can you look for in the specifications to tell a good meter from a crappy one ...
5
votes
1answer
1k views
How to test brushed motor rotor coils with a multimeter?
I have a Blendtec blender that just decided to break on me. The blender has an electric brushed motor that looks like this:
http://www.ifixit.com/Teardown/Blendtec-Total-Blender-Teardown/1128/2
When ...
5
votes
2answers
224 views
Digital multimeters battery placement
Apologies if this is a ridiculous question.
I'm completely new at electronics, and so I just got my first multimeter - a pretty cheap one, a Draper Digital multimeter. Got my first problem with it as ...
5
votes
2answers
518 views
What units is my multimeter using to measure batteries?
I have an old, cheap multimeter (Dick Smith Electronics, Q-1420) with a battery testing mode (presumably testing the battery under load).
When I put it into 1.5V battery testing mode, and connect it ...
1
vote
3answers
165 views
A device that runs on AC current it's voltage inside is measured by always turning the multimeter's knob to AC voltage:same for DC right?
I've bought a cheap multimeter and it's not automatic. I've to manually rotate the knob.
I live in North America. AC current is used in my home. Does this mean I can always measure voltage by turning ...
2
votes
1answer
140 views
Are those some kind of timed-resetting fuses in DMMs?
Yesterday, I did something dumb, in a hurry. I wanted to check the AC voltage at the terminals of a hair-dryer, to determine the voltage being applied to the terminals of the AC fan behind it. ...
4
votes
1answer
743 views
How does autoranging work in a multimeter? What is the circuit?
I was curious how this is done. It seems you would have to vary the voltage and current to measure resistance from 1ohm to 10Mohm.
5
votes
3answers
155 views
How can I tell if a particular multimeter measures AC with RMS or Average
I require a multimeter measuring RMS but unfortunately know little on the subject and am unable to tell which method one uses from it's description.
Its states:
MAX. Voltage between terminals ...
7
votes
1answer
304 views
What are these banana plug connectors used for?
These mate with one another (in the obvious male-to-female chain). They seem to be male-to-female banana plug adapters. Maybe I am being naive, but these seem useless. What are these useful for in ...
1
vote
1answer
206 views
Ripple factor detection and measurement
How to measure ripple factor automatically for a pulsating dc output(0-300 v)?
1
vote
1answer
701 views
Repairing a digital multimeter?
don't know if this is the right place to ask such a question but i'll try.
I opened up my DMM to check fuses. Now I would like to close it but before I can do this I have to put in the right place the ...
12
votes
4answers
2k views
What not to do with a Multimeter
So I just bought and installed a new fuse for an analog multimeter I scored for free and now it works like a charm. The new fuse is the same rating as the blown one I found inside, which is 0.5A ...
0
votes
0answers
113 views
When I turn on my multimeter it wait one second and turns off [closed]
I'm newbie and some years ago I bought a multimeter.
In recent days I started again to build circuits and found that my multimeter doesn't work properly.
When I turn it on, the display shows ...
1
vote
1answer
99 views
Power supply requirements for TM355
I've recently got hold of a second hand Thandar TM355 bench multimeter. It can be supplied by either 6 "C" cells or there's a 2.5mm barrel plug for power. Unfortunately, the service manual doesn't ...
1
vote
3answers
156 views
Resistor before voltmeter
Let's say I take my multimeter and measure the voltage across the poles on my battery, I get some reading X volts. I then put a resistor between one terminal and the adjacent probe, this resistor has ...
5
votes
5answers
282 views
Why do DMMs have a capacitor on their AC measurements?
see answers to this question.
Is a capacitor really necessary? And wouldn't it make measurements frequency-dependent?
2
votes
4answers
2k views
Wrong multimeter readings measuring 12V lead acid battery
I just got my first multimeter and when I measured a 12V 1.2ah lead-acid battery I get AC 28.8V and DC 13.4V. Is this normal?
In addition I tested an AA 1.5V battery and I got 2.9V (AC setting 200) ...
2
votes
3answers
587 views
How usable can results of measuring MOSFET resistance with a multimeter be?
When the resistance of a MOSFET at a certain gate voltage and current is needed, the correct value is ordinarily obtained by reading the datasheet for specified values.
Since a MOSFET is supposed to ...
