What is inductive load and resistive load

What is resistive load appliance? What is inductive load appliance?

Resistive Load is a kind of electrical load which is characteristic of not having any significant inrush current. When a resistive load is energized, the current rises instantly to it’s steady state value , without first rising to a higher value.
An electrical load in which voltage and current are converted to energy in the form of heat. For example, an electrical heater, candescent bulb. mobile,laptop, TV, LED light, toaster, oven, hot plates, curling irons, coffer makers, video player, small printer, water dispenser, electric cooker, etc.

Inductive Load is an electrical load which pulls a large amount of current ( an inrush current) when first energized. After a few cycles or seconds the current settles down to the full-load running current.
The time required for the current to settle down depends on the frequency or/and the inductance value of the inductive load.

It means the large power electric appliance whose working principle is the electromagnetic induction. Like motor, compressor, relay, etc.
For these products, the start-up power is much higher than the rated power (about 3~7 times).For example, the rated power of the fridge is 150w, but its start-up power is higher than 1000w.

The extent to which the voltage and current peak at separate times is quantified by the power factor. For purely resistive loads, power factor equals 1. Increasing variance from this value indicates decreasing amounts of real power available for work.

Types of Load Bank Elements

Resistive Load Elements

The most common load banks use resistive load elements. Resistance is generated when current passes through conductors in a load bank element, producing heat and placing a corresponding electrical load on the power source. Resistive load elements can produce precise amounts of load at a power factor equaling 1.

Resistive load elements generate large amounts of heat that must be quickly dissipated to prevent overheating. Consequently, load banks use forced air to cool resistive elements, which is provided by a dedicated power circuit and one or more blowers.

Loading the prime mover, typically a diesel engine, can identify problems in its fuel, exhaust, cooling, and other systems. Because resistive elements operate at a unity power factor, they do not test the reactive power produced by a power source. Because most facility power distribution systems operate at a lagging power factor near 0.8, a resistive unit can apply load up to 100% of a generator’s nameplate power kW rating. However, a resistive load element will not test the generator against any inductive or reactive load on the circuit.

Inductive Load Elements

Known also as reactive load elements, inductive elements use wire coils to create inductive fields. The power used to create and maintain these fields loads the power source under test. Compared to resistive loads, inductive load current peaks after voltage. Consequently, inductive coils produce lagging power factors.

Because they produce lagging power factors, inductive load elements are used whenever the power factor of a test load must be reduced. For instance, the power factor in a hospital’s power distribution system may be near 0.8. However, during generator tests, load banks may be used instead of live building load to avoid disrupting power to the facility. Because resistive load banks provide a power factor of 1, they are unable to test a power source at its rated kVA. Adding an inductive load bank can adjust the power factor to the value needed for full-capacity testing.

Capacitive Load Elements

Capacitive load elements use capacitors that store electrical charge. They resist changes in voltage, which causes current to peak before voltage during each electrical cycle. As a result, capacitive load elements provide a leading power factor, and can be used to raise power factors of circuits.

Combined Load Element Designs

Combined load banks typically provide both resistive and inductive load elements in a single enclosure. For generators, this enables testing at 100% of kVA rating. The resistive and inductive load elements may be independently controlled to produce purely resistive or inductive loads or to adjust the power factor as required.

Notably, load banks with more than one type of element can accommodate the widest range of applications. Combined load banks are used to test turbines, switchgear, rotary UPS, generators, and UPS systems. These load banks can be especially suited for use by rental companies, which may be required to accommodate different load types as equipment is relocated from site-to-site.

Summary

Load banks are available with resistive, inductive, and capacitive load elements. Resistive units test power sources without changing the power factor. Inductive and capacitive load elements can be used to simulate for non-unity loads and to adjust the power factor of circuits. Load banks with combined load bank elements offer the greatest range of functionality, which can be especially suited to applications where load banks are moved from site-to-site. For further information please contact us.

The main difference between Resistive Load and Inductive Load is resistive load converts the electrical energy into heat whereas the inductive load converts the electrical energy into magnetic energy. There are ao many differences between inductive load and resistive are available. Let's know all of them.

Some examples of resistive load are electric heater, filament bulbs, etc. Resistive loads are very constant in nature. They only oppose the flow of current and do not make any changes in the voltage and current.

Resistive load generally produces heat when an electrical supply provided to it. Resistive loads are very simple in construction also. They only have a coil of conductive wires. The main function of the resistive load is to produce heat and it depends upon the length and cross-sectional of the wire. Also, it depends upon the duration of the current flow and its magnitude.

Some major properties of a resistive load are,

They do not make any phase difference between voltage and current.
The resistive load cannot store electrical energy, in fact, they waste electrical power in form of heat.
Resistive load always shows the same characteristics for both AC and DC supply.
Resistive load always causes a unity power factor.
The resistive load cannot produce reverse power to the circuit.

Read Also: Resistance Reactance Difference, Effects, Example, Application

Some examples of Inductive Loads are Electric Motor, Induction cookers, etc. Inductive loads are those which not constant in nature. Their characteristics change with changes in the nature of the power supply. In fact, they can change the nature of the power supply. Inductive loads are the more power-consuming or heavy load among others because they can drive the mechanical load also. Inductive load not constant in nature also, unlike a resistive load it can take any amount of current according to its applications.

Some major properties of an Inductive Load are,

The inductive load can make a phase difference between voltage and current.
Inductive load shows different properties for AC and DC. In fact, its properties depend upon the frequency also.
The inductive load can store electrical energy in form of a magnetic field for a very short time.
Inductive load always causes a lagging power factor.
The inductive load can produce reverse power to the circuit.

Read Also: When Capacitor store more Energy Series or Parallel connection?

Resistive Load	Inductive Load
It converts electrical energy into heat energy	It converts electrical energy into magnetic energy
It cannot store electrical energy	It can store electrical energy in form of a magnetic field
It cannot change any phase difference between voltage and current	It can change the phase difference between voltage and current
It waste much electrical energy in form of heat	It waste electrical energy very less due to its internal resistance only
It cannot generate reverse power to the circuit	It can generate reverse to the circuit
It makes power factor unity	It makes power factor lagging
It shows same properties for both AC and DC power Supply	It shows different properties for AC and DC Power Supply