What Is an Electromagnetic Counter?
An electromagnetic counter is a device that counts by the operation of an electromagnet built into the electromagnetic counter. The electromagnetic counter is connected to an actual circuit, and the fluctuating value of the electrical signal is changed to a mechanical force by the magnet to be counted, so it operates only with external power. Electromagnetic counters can be classified into two types: preset counters, which act as switches to operate devices according to the counted values, and total counters, which output only the counted values.
Applications of Electromagnetic Counters
Electromagnetic counters are mainly used in production plants for a variety of products. When selecting electromagnetic counters, it is necessary to consider the accuracy of counting, the amount of current and voltage of the circuit to be connected, ease of maintenance, connectivity, vibration resistance, and dust resistance.
Examples of the use of electromagnetic counters are shown below.
- Counting product shipments
- Counting the number of empty cars in a parking lot by counting the number of cars entering and exiting the parking lot
- Measuring the number of rotations by connecting to a rotary encoder
- Counting the number of products to be packed in the bagging process
Principle of Electromagnetic Counters
The following is an explanation of the principle of operation of electromagnetic counters. An electromagnetic counter consists of wiring to connect to a circuit, a coil, an electromagnet, and a counter whose numerical value changes according to the movement of the electromagnet. In the case of a preset counter, a device is included to transmit the numerical value of the count to other devices.
During operation, the current flowing from the circuit flows into the coil. The current flowing through the coil causes the coil to generate a magnetic field. The magnetic field causes the electromagnet to move, advancing the count of the counter. If the current is in the form of a pulse wave, the current flowing in the coil changes with time, and the magnetic field changes accordingly. In this case, the force acting on the electromagnet changes, causing the electromagnet to fluctuate periodically, and the counter counts according to the fluctuation value.
In the case of a preset counter, the count is always sent to another control device, and the control device operates a switch to start or stop the operation according to the count.