Table of Contents
Can you have a voltage but no current?
Voltage attempts to make a current flow, and current will flow if the circuit is complete. It is possible to have voltage without current, but current cannot flow without voltage.
When does a voltmeter read zero?
Voltmeters typically read zero volts when measuring between points of equal potential. Closed switches and connected wires are examples of components that, when energized, are of equal potential. Voltmeters typically read line voltage when measuring between points of different potential.
How do I know if my multimeter is bad?
If it’s very low (close to 0 ohms), it’s still good. If it’s very high (open circuit), it’s blown. A 200 mA fuse should have a very fine wire visible inside the glass. If it’s completely clear, the wire is gone (blown).
Why is there no voltage in a wire?
Because there is no circuit element such as a resistor in-between your leads to drop the voltage, the voltage difference is zero, and you will get a voltage reading of zero.
What is the relation between voltage and current?
The relationship between voltage, current, and resistance is described by Ohm’s law. This equation, i = v/r, tells us that the current, i, flowing through a circuit is directly proportional to the voltage, v, and inversely proportional to the resistance, r.
How do I know if my multimeter is faulty?
If your multimeter powers up but you aren’t getting accurate measurements you may have faulty test leads. Set your multimeter to read resistance and touch the test probe leads together. It should read zero ohms.
How do you test voltage and current with a multimeter?
The setting for testing voltage in an AC circuit is typically marked V~, ACV, or VAC. To test voltage on a DC circuit, set the multimeter to V–, V—, DCV, or VDC. 2 Set the multimeter to measure current.
What does the squiggly line mean on a multimeter?
Reading the Dial Settings Test AC or DC voltage. In general, V indicates voltage, a squiggly line indicates alternating current (found in household circuits), and a straight or dashed line indicates direct current (found in most batteries). Set the multimeter to measure current.
How many ohms should a digital multimeter read?
It should read zero ohms. If you have resistance ratings of over one ohm or the reading is erratic, you should be able to fix the problem by replacing the probe leads. If you still haven’t been able to address the issue the next step is to disassemble your digital multimeter.