50 Watt Rheostat

50 Watt Rheostat – High Power Rheostat Example
Rheostats have been used in industry for over 50 years. A rheostat has the electrical characteristics of being able to offer an adjustable resistance specified at time of ordering the rheostat and being able to dissipate significant power – 50 watts in the case of the APR50 rheostat. This is useful in applications such as:

motor control
lighting control
industrial controllers
sound level control
laboratory test setups

Rheostat Specification
Parameters used to specify a rheostat include the following:

Resistance tolerance – typically +- 10% in the case of the APR series rheostats.
Insulation Resistance – Typically 100M ohms at 500 volts d.c.
Rotational […]

October 3rd, 2014|Power Resistor, Resistor Applications, Wire Wound Resistors|

100 Watt Power Resistor Example

100 Watt Resistor Application And Specification
We had a recent enquiry for a power resistor that was to be used in the mining industry for a braking resistor for a conveyor belt system used in a coal loading terminal in Newcastle. The motor requiring the braking resistor was slightly unusual in that it was a d.c. (direct current) motor. The resistor required had the following requirements in its specification:

3.9 ohm resistance
Maximum current rating 4.5 amps (d.c.)

Using basic resistor theory we determined that the most appropriate power rating for the resistor would be found by using the formula Power (dissipated in the resistor) = […]

September 8th, 2014|Applications, Power Resistor, Resistor Applications, Wire Wound Resistors|

200 Watt Power Resistor

200 watt rated power resistors  are commonly used in industry in a wide range of applications including:

resistor load banks
dropping resistors in large power supplies
power conversion circuits
braking applications

Tubular power wire wound resistors are often considered to be the ‘standard’ in high power resistors as they offer a ‘tried and tested’ solution and offer high reliability and low cost. The HO Series power resistor is often used when a 200 watt rated resistor is required. This resistor specification includes:

200 watt rating
267 mm ceramic former length
29 mm ceramic former diameter or 33 mm when coated
Mounting feet centres are 292 mm
For the standard fixed power […]

Laboratory Resistor Applications

The Laboratory Resistor – Invaluable In Many Applications
The laboratory resistor (also referred to a a slider resistor) has been used for a convenient way to achieve and easily adjustable power resistance for over 50 years. Whereas a wire wound potentiometer offers a variable power resistor via a rotary form of adjustment, the laboratory resistor offers a way of adjusting the resistance via a linear form of resistance.

Many educational institutions such as universities, technical colleges and high schools use laboratory resistors in their electrical and electronics courses as they allow students to easily and accurately set a specific resistance value via the sliding […]

July 23rd, 2014|Power Resistor, Resistor Applications, resistor theory|

Wirewound Resistors – Basic Resistor Principles

Understanding Critical Parameters In Resistor Selection – Ohms Law
Going back to college fundamental physics is helpful in understanding the most commonly used parameters used in specifying wirewound and power resistors. Good engineering practice will generally mean that a certain degree of ‘over specifying’ will result in long term reliability and performance of the final product – be it a motor control circuit, power supply, resistor bank, heating or cooling appliances or printed circuit board control circuitry.

Resistance – Ohms Law

Ohms law is possibly the most fundamental equation taught in electrical engineering. It is the foundation principle used to determine the relationship […]

Wire Wound Potentiometer Reliability

Wire Wound Potentiometer Reliability
Potentiometers have been used in electronic circuitry since the early 1900’s. The mass production of valve radio’s in the 1920’s lead to a demand for reliable, cost effective variable resistors for applications such as tone controls and volume controls. Carbon potentiometers were often used as the resistive material(and still are) for low wattage applications. The potentiometer ‘wiper’ – the moving ‘arm’ that connects to one of the potentiometers terminal was often the cause of unreliable operation in early manufacturing operations of potentiometers. The wiper must make an effective and highly reliable contact with the resistance element during […]

May 27th, 2014|wire wound potentiometer|

Rheostat Used In Remote Irrigation Project

The APR series of rheostat has a long history of reliable operation in many applications requiring a rugged, easily mounted rheostat that can offer variable resistance adjustment and high power ratings. Selecting the appropriate rheostat is a matter of determining the power that has to be ‘dropped’ across the rheostat winding and the required resistance of the rheostat.

Available Rheostat Power Ratings

The APR series has 5 available power ratings giving engineers flexibility in selecting the most appropriate rating for their product or design. These ratings available are 25 watt, 50 watt, 150 watt, 300 watt and 500 watt. Power dissipation of the […]

May 7th, 2014|Rheostat|

Panel Mount Resistors

The addition of aluminium housed resistors to our range of resistors means that our customers have an increased option when it comes to resistor selection for their application.

Terminology: Panel mount resistors are also referred to in the electronics industry as ‘panel mount resistors’ and ‘aluminium housed resistors’.

Applications; This style of wire wound resistor is used where a small physical size is required (relative to the power rating of the resistor) and a rugged construction of the resistor is required.

Mounting And Heat Sinking: The aluminium housed resistors are typically mounted on a suitable heat sink material by way of the mounting […]

April 7th, 2014|metal clad resistors, Resistor Applications|

5 Watt Wire Wound Potentiometer

We have had several enquiries for a 5 watt rated wire wound potentiometer for applications ranging from motor control, light dimming, audio equipment and industrial controls. The standard AW potentiometer is rated at 3 watts but can be used in a 5 watt application. The way we achieve a 5 watt rated wire wound potentiometer is to use a dual gang AW potentiomer with the terminals paralleled up to achieve the higher wattage rating required.
Available Resistance Range
Because the AW potentiometer has a resistance range from 1 ohm to 50k ohms (with a linear taper) when the dual gangs are connected in […]

March 11th, 2014|wire wound potentiometer|

ASW Series Precision Resistor Used In Linear power Supply

The ASW 5 precision wire wound resistor is rated at 6.5 watts and has been used throughout the Australian electronics manufacturing sector for 30 plus years. This series of resistor has been used in many applications where tight tolerance, high inrush of current and long term reliability of operation are required.
400 Watt Linear Power Supply Application
A recent use for this resistor has been in a locally designed 400 watt linear power supply. The trend in power supply design over the last 15 years has been more towards switch mode technology as high efficiency power supply operation is possible and minimal […]

February 19th, 2014|Applications, Precision Wire Wound Resistor|