Methods of Ground/ Earth resistance measurements on existing systems

It is vital to maintain good ground in a system. In order to ensure that, ground resistance measurements and tests are conducted on existing earth electrodes at periodic intervals after their installation. This ensures the resistance in the ground is at an acceptable level and is maintained. Here are the different methods of ground/ earth … Read more

Soil resistivity measurement methods

One of the key elements affecting ground resistance is soil resistivity. Soil resistivity measurements are conducted before setting up an earthing system, in order to ensure an effective earthing. Good soil models are the basis of all grounding designs and they are developed from accurate soil resistivity testing. The ground/earth resistance measurements are conducted to … Read more

Power consumption and energy usage of humidifiers

Humidifiers are used to increase the humidity in a confined space. They can be used to humidify living rooms and ventilators can be used to treat dryness. A typical household humidifier consumes a power of 25Watts. The energy usage of humidifiers can be calculated below: Enter the wattage, hours of usage, and cost per kWh. … Read more

Power consumption and energy usage of exhaust fans

A typical household exhaust fan consumes 40 watts of power. The energy usage of an exhaust fan purely depends on how many hours they spin. The energy usage of exhaust fans can be calculated here. Enter the wattage, hours of usage, and cost per kWh. The energy usage calculator for fans gives you the total … Read more

Grounding transformer or Earthing transformer

Grounding transformers are used to obtain a neutral when an existing delta-connected or ungrounded systems are to be grounded. These transformers provide a path for the flow of fault currents during unbalanced ground faults. They can be found in transformer substations where neutral might not be available as the transformer windings are delta connected. Types … Read more

Dual-element time-delay fuses

Time-delay fuses can provide overload and short circuit protection while overcoming momentary current spikes. They are used for the protection of motors and transformers. The time-delay characteristics of these fuses typically allow them to be sized closer to the running rated full load current of the loads. Time-delay fuses are also known as slow-blown fuses … Read more

Interview questions on Modbus

Below is the list of the most important interview questions on Modbus: 1. What is Modbus and how does it work? Modbus is an application protocol that defines rules for organizing and interpreting data and is essentially a messaging structure that is independent of the underlying physical layer. It is an open-source protocol and is … Read more

Difference between AC contactors and DC contactors

The AC contactors differ from the DC contactors in their construction, arc extinction, and usage in a circuit. In this article, let us discuss the major differences between AC contactors and DC contactors. Contactors are electrically controlled switching devices. They are used to switch electric motors, lights, reactors, capacitors, heating loads, EV charging systems, UPS, … Read more

Resonant grounded system (Ground-Fault Neutralizer)

A resonant grounded system can significantly reduce the ground fault currents. This grounding system basically consists of a tuned reactor connected between the neutral and the ground that resonates with the line-to-ground capacitance of the system so that the magnitude of the ground current is reduced. This reactor is knowns as a ground-fault neutralizer or … Read more