A voltmeter should be a must-have for every installer. It is a relatively simple device, but extremely practical and reliable. It is used to measure electrical voltage, one of the most important parameters of every electrical installation. How to connect a voltmeter to a circuit? We present the most important information that is worth reading.
Voltmeter and ammeter – differences
A voltmeter and an ammeter are the two basic devices that you most often encounter when working on electrical installations. These are devices that are used to measure current parameters, and the most important difference between them is how they are connected to the electrical circuit.
In the context of these devices, it is worth mentioning that electricity can be measured in two different ways - through current or voltage. A voltmeter is used to indicate direct (DC) or alternating (AC) voltage, while an ammeter is a device that measures current.
An ammeter is connected to an electrical circuit in series. It has the ability to measure a small amount of current, which is expressed in milli or microamps. The resistance of the ammeter is relatively low. Thanks to this, it does not block the flow of current in any way, so the device shows its actual value.
The voltmeter is connected to the circuit in parallel. Its polarity is the same as that of the ammeter. In practice, this means that the positive pole should be connected to the positive polarity of the power supply, and the negative potential to the negative polarity. As for the resistance of the voltmeter, it is much greater than that of the ammeter. The value of an ideal voltmeter in theory is equal to infinity. Due to such high resistance, current has less chance of flowing through the device, so a relatively accurate voltage value is measured at a given measurement point.
Check out ammeters and voltmeters at the Onninen wholesaler
How to connect a voltmeter to a circuit – tips
Voltmeters are devices that can be divided into two basic groups - digital and analog. They differ in construction, accuracy and purpose, but their main task is the same, i.e. measuring voltage in an electrical circuit. There are also multimeters, i.e. multi-purpose devices that are used to measure both voltage, current and resistance. Multimeters used today are digital devices equipped with LCD displays.
When connecting a voltmeter to an electrical circuit, the most important thing to remember is to do it in parallel. In practice, this means that the voltmeter tips should be placed directly on the element on which we want to measure the voltage. The red end of the voltmeter should be connected to the positive pole and the black end to the negative pole. The first test lead in the device should be placed in the socket marked with the letter V, and the black one - in the socket marked with the letters COM or GND. If, after taking the measurement, a negative value appears on the display, it is worth checking whether the terminals have not been connected the other way around.
When connecting a voltmeter to the circuit, it is also worth remembering to ensure sufficient safety. The most important thing is that under no circumstances should you touch the metal terminals of the voltmeter. Not only can this significantly distort the result, but at higher voltage it can even shock the person performing the measurement. When operating a voltmeter, hold only the insulated parts.
Voltmeters available at the Onninen wholesaler
In the Onnien wholesale offer, you can find a very wide range of advanced voltmeters for various applications. We offer, among others: modular voltage meters, such as the Spamel 1F modular voltage meter , which are perfect for measuring voltage values in a three-phase network. In the Onnien electrical wholesale store , you can also find advanced digital meters, such as the Promet NEF30MC digital meter and many other professional products that will be an invaluable help during the work of every installer or electrician. The offer includes only top-shelf devices that are characterized by above-average durability, high quality of workmanship and excellent accuracy. The offered voltmeters are professional products from manufacturers such as: Emas, Promet and Spamel. We invite you to familiarize yourself with the entire range and choose a device perfectly tailored to your needs and adapted to specific tasks.