Search Engine www.edaboard.com

# Multimeter Circuit

93 Threads found on edaboard.com: Multimeter Circuit

## SMPS input current measument

Hi all, This is Mohan, Actually i tried to measure input current of smps(3 phase input), to make smps automation circuit,we have used a 1 ohm resistor to the the series of all the three phases of smps ,normally when i measure in multimeter i saw 40mA at the smps input when i measure(voltage) across the 1 ohm resistor i got 0.04v so when i use f

## RC Snubber for BTA26-600 Interfaced to PIC16F73 for AC Single phase motor control

With the snubber of 1nF/250V(shown by multimeter) and 1.5Kohm is not allowing the PIC to control the motor Your schematic is showing a different circuit. Anyway, which behavior do you exactly observe? 1 nF is about no snubber. Think about capacitors in a 47nF to 220 nF range. As an additional point, the crossing detector in yo

## How to perform DC channel estimation

Hi everyone, I'd like if someone can help me to understand how to perform the DC channel estimation in terms of noise, interference etc with some instruments (multimeter, spectrum analyzer..) of a car. I thought to make these measures using the cigarette lighter of a car to sense the entire circuit. In a few words I need to "see" how i

## How to perform DC channel estimation

Hi everyone, I'd like if someone can help me to understand how to perform the DC channel estimation in terms of noise, interference etc with some instruments (multimeter, spectrum analyzer..) of a car. I thought to make these measures using the cigarette lighter of a car to sense the entire circuit. In a few words I need to "see" how i

## What is wrong with this radio circuit

A diode in series with a capacitor cancels the diode current. Operating a 200 MHz OP without any bypass capacitors is really a bad idea. Generally you'll start verification of circuit by measuring all DC levels (e.g. against common ground) with a multimeter.

## Kaise SK-6111 help needed

Reference existing thread: hi I need kaise sk6111 circuit pic or schematic for repair this digital multitester - I need 1 pic from front and back of this multimeter

## Simple constant current source question

I have to agree with Bob Pease (who am I to disagree :0) ) , breadboard testing is a must. I built the circuit last night. Worked surprisingly well , probably not far off the simulation. I did't have a high quality multimeter with me to accurately measure uA accurately though. Will take a better meter home tonight and try and do some accurate meas

## How to achieve 5A short circuit and maximun current for series voltage regulator?

106337 The figure shows multimeter at the output is in Ammeter mode which i think it functions as short circuit for the system. Referring the picture, I attached. I have designed a series voltage regulator that can convert AC source to DC source (range from 0 - 20V). However, I could not achieve 5A maximum curr

## Measuring total current used by circuit with multimeter problem

You won't get a reading with blown fuse. So more likely it's just multimeter voltage drop. Measuring current directly at the battery terminals should work better.

## AC Voltage Measurement Error

Hello Every Body, I am making a voltmeter that can measure the AC voltages from 0 VAC to 115 VAC accurately using microcontroller. Below is the circuit for converting AC to DC for microcontroller. I am using my multimeter to cross checking my voltmeter. Now I am having a problem that when I increase the AC voltages l

## WTA how to calculate the the battery life span for a circuit ?

You cannot calculate the current used by the buzzer. Its datasheet tells how much current it uses at a certain voltage or you can measure its current with a multimeter.

Did check voltage levels with an oscillocope or average values with a multimeter? Did you verify correct supply voltages? Would be better to see a schematic.

## simple circuit to detect a short circuit?

Like the buzzer in the multimeter to detect if a wire is ok or not it should beep if the resistance between the probes less than 60 ohms thanks

## Dell XPS M1330 Mainboard problem

Do you know electronics? Do you have instruments to check the circuit? such as oscilloscope, multimeter, logic probe etc. It seems you still have something shorted. When you connect the battery, connector over heats means you still have short somewhere, something draws a lot of current, you have to troubleshoot to find out what is causing that, whi

## Any idea if this circuit attached to the MCU pinout is correct?

97325 Hi. The attached image is a section of a Car Parking Assist device. Not sure if it is correct but I traced the connections on the board from the MCU pinout to the data out pin of the device using a multimeter. I am not 100% sure if the transistors are BJTs or JFETs cos they are all SMD devices, but am sure they ar

## 89S52 , ULN2803 & 7 segment display- Weird behavior !!

Heyy i am driving 4inch 7 segment common anode display using 89S52 & ULN2803 !! normally my circuit works perfectly ,,but whenever i touch any pin of ULN2803(which is used for driving 7 segment display) with my multimeter's probe, the respective segment switches off !! ??? & this happen with every other segment when i touch respective pin of

## Comparator circuit misbehaviour

The opamp has such a high gain that when the circuit is built on a breadboard then it oscillates. When oscillating, its output is switching high and low at a high frequency. Your multimeter is measuring the average DC output voltage which is near half the supply voltage. Usually, a comparator circuit has hysteresis (a little positive (...)

## Diode ORing voltage measurement

For the below circuit, I have placed multimeter +ve probe at 'B' wrt GND and measures 4V against the expected value of 0V. Hence I have terminated the 'B' end with 10K to GND temporarily before taking the measurement and reads 0V. Why this happens? What happens to the anode of D2 while I connect a multimeter to 'B' end wrt GND ? (...)

## Current on my voltage regulator

Your multimeter will probably have a 10A setting but you might have to change the jack - look at your multimeter.

## 4 probe copper foil resistance measure + AD623 instrument amplifier - output ?

I can't get my circuit to work! What I want to do: Measure the resistance (in fact voltage) of copper foils with the 4 probe method and amplify the output with i.e. an AD623 (tried INA126 too) instrumental amplifier. I attached a circuit of about what I am using. Just to get some figures I checked with a multimeter (which is probably (...)

## Input Impedance of the Circuit

Input impedance is a differential quantity dV/dI rather than the ratio of input voltage and current V/I. The shown multimeter measurement will mainly reflect the OP input current in combination with the meter's test voltage. The real impedance will be around the datasheet value of 10E12 ohms and not depend much on the amplifier closed loop

## OPAMP simple circuit problem

circuit is unstable. It oscillate at 240kHz. Adding RC as godfreyl proposed makes it stable. If your multimeter readings differ you may suspect oscillations of a circuit. Next time use oscilloscope if you can.

## Problem with My circuit

Connect to pin 3 and 8 of the 7-segment display. kindly see the image. Have you seen the 7-segment display in your crystal ball or are you just guessing? There are about 10 different 7-segment pinouts in use. You'd either refer to a known type or figure out the pinout by using a multimeter.

## How I can add a cooler with this circuit?

if u want to drive a 12V dc fan....u can use a simple transistor driver circuit... 1. read the resistance of fan from multimeter... 2. calculate value of

## Photoelectric sensor fast switching circuit for Micro controller input

I just reduced the voltage alone and check on multimeter, it was switching. How did you "reduce the voltage"?

## Why is base current not what it should be?

87807 My multimeter shows: Ib=218\muA why? But my calculation shows, it should be: 8.5\muA I used the formula: Ib=(3.1-0.7)/(10k+271k) [I have \beta What is the problem? Please help

## Voltage Drop measurement using Digital Multimeter in a 5A live circuit

Consider the below circuit with 28V supply and electronic load set at 5A Constant Current mode. What voltage drop would I expect when I connect a digital multimeter between A & B ? V(AB1)= V(R6)+V(R8)+V(R9) What voltage drop would I expect when I connect a digital multimeter between C & D ? V(CD1)= V(R7)+V(R8)+V(R10) Consider (...)

## Resistance measurement using multimeter

Many multimeters work by injecting a small current and reading a voltage. A circuit with current already flowing will jack that reading because the total current is not what the injected current and its corrolary, assumed scale factor are. If you're trying to measure resistance using the resistance function. In such a case, you would need

Hi, I am trying to make a precise voltmeter(upto 1mV) using a 16bit ADC [ ADS7825 : and a pic micro. Which I will calibrate with an bench multimeter in my lab. I have interfaced the ADC in parallel mode. And I am getting the output almost as desired.. I have made the circuit on the breadboard, an

## Measuring voltage of capacitors

I've built a variable voltage DC power supply circuit using an SCR, rectifier and 160v 33uF capacitor. I've got a 7-150v DC voltmeter hooked up to display the voltage. It always reads 160v, even if I use my multimeter. If I remove the capacitor, I get true voltage readings. How big of a load do I need on it to get the correct voltage to display

## Weird Multimeter Behavoir???

Hello, Is it normal for a multimeter when it's set to measure voltage and it's probes not touching anything to show a floating reading of fractions of volts? This happens with Agilent U1253B. Any idea?

## Can Microcontroller circuit can be powered by using a 9V battery or a mobile charger?

Dear Friends, Can we power a 89C51 circuit using a 9V multimeter Battery or a Mobile Charger? It is a daily occurrence, to power PCB with uC from 12V, 9V or mobile charger 5V, even with 1,5V. You can power every uC with 1,5V battery as source of power. How? In manufacturer datasheet for each part, especially

## testing ohms law - issue

As jeffrey said measuring with an ohm meter is a bad idea because it applies a know current and measures the voltage and displays the resulting resistance value by applying the ohms law. Doing that in a live circuit not only interferes the circuit operation and the measuring but can produce damages to either the circuit or the (...)

## Choosing the right fuse

All depend what fuse should protect, what circuit and device. What is inrush current? Do you have some inductance in circuit? If your circuit have max 4A of current then fuse must be higher then 4A. Best use multimeter (ampermeter) to monitor current. You can use slow or fast fuse depence from

## need help with 13001 transistor in Mobile charger.

Hello Ayazhaider, My checking method is as FOLLOWING: I set multimeter on (Alarm / connectivity / diode) testing. This setting is ok. then connect red and black probe on emitter and collector. then reverse. If now you don't have any reading on your display the transistor has no short circuit. Now, tes

## switch pressing Usart identification problem

HI Please check with your circuit using multimeter, while pressing the button the voltage gets dropped or not, i not sure about that syntax of your compiler, but u have to scan the input level of pin by using the trisb register....

## help me due to error in reading phothodiode as analog ensor

hello, maybe impedance input of analog input is too low. try to add a buffer AOP . can you measure the voltage accross photodiode with a multimeter while a big source of light is on it ?

## how to check a pwm IC with multimetr if it is woking or not ,in general

Without a lot more detail on the signal levels and circuit you're trying to perform the measurements in, here's a basic concept that might give you a few ideas. Your multimeter is probably far too slow to follow the rise and fall of the PWM signal, but you can get an idea if the PWM circuit is working by looking at the average output (...)

## resistance measuring circuit in digital multimeter

can someone help me with a resistance measuring circuit used in digital multimeter

## Simple Diode Circuit for half wave rectification

The multimeter SHOULD be set to DC but there is a catch.... what the meter reads will depend upon the type of meter. What you are seeing is an 'average' of half wave rectified AC, in other words half sine cycles with gaps between them so the reading is lower than expected. Some meters will give different readings though, depending on how quickly th

## Testing Zener - With a Multimeter

Hi, I came across a faulty Zener diode in a SMPS. On the same board I saw one Zener, with the same colour code. A reverse bias it, with my Fluke 289, I thought that with was a 2Volt Zener since I saw on the meter 2V in diode mode. Wrong! The multimeter does not tell us the reverse voltage of the zener! I have made this mistake an hope tha

## How to make thermometer using digital multimeter???

Simple circuits.............. Module thermometer, using the ic lm35 Module thermometer, temperature meter for digital multimeter using the ic lm35 | Xtronic Free Electronic circuits and Informations MAXIM MAX 6610 Temperature Probe for Digital Mult

## Help required in identifying component

Hi, Is there any thing written on the board on its location? Can you put an image here of that area where it is located? Or when the power is off to the circuit and the component is cold check it with multimeter to see whether it shows to be a Diode.

## help required with closed circuit DC jack

using multimeter you can test it.. the pin inside the connector is shorted to the pins outside the connector... and the internal body is connected to other pin visible outside.. the third pin is shorted to either the pin or the internal circular surface.. the pin is positive and the internal body is ground.. so when you mount the pins shorted

radio works on ferrite antenna. The systems high frequency and intermediate frequency are original. Only low frequency amplifier was changed into a circuit based on UL1497. To start the receiver, a multimeter, voltmeter and signal generator are needed. In absence of the s

## LM386, MIC Help required

You can connect a speaker to the output of lm386 after the capacitor and to the ground to monitor output. Pin 5 should be at 1/2 Vcc if circuit is build correct. The reading you are getting is charging of 220uF capacitor through multimeter.

## resistance short ckted but only in one direction (multimeter)? is this possible?

It is possible, because when you change the polarity of the zener diode, the current becomes flowing through the diode and acts like a short circuit for your resistance. Therefore no resistance is detected by the multimeter. In fact, you can use this property to test diodes.

## how zener diode behaves if it is not working?

check the forward and backward resistance using multimeter.. if both are same then the diode is bad... But this should be checked by removing the diode from the circuit usually,....

## plz help me , digital multimeter using microcontroller

dear all, i m doing on project digital multimeter using microcontroller. the parameters of multimeter is following.. 1-dc voltage 2-dc current 3-ac voltage 4-resistance 5-capacitance 6-frequency how can we design the circuit of all parameters?????

## virtual terminal in proteus

You can find the virtual terminal in the multimeter icon directly below the current probe (I) in the left side icons. Place it in your schematic and connect the Rx,Tx lines. You can also double click it to change the settings Alex