Thermostat

A thermostat simply switches the heating system on and off as necessary. It works by sensing the air temperature, switching on the heating system when the air temperature has been quickly reached.

Turning a room thermostat to a higher setting will not make the room heat up any faster. How quickly the room heats up depends on the design of the heating system for example the size of the boiler and radiators. Neither does the setting affect how quickly the room cools down. Turning a room thermostat to a lower setting will result in the room being controlled at a lower temperature, and saves energy.

The heating system will not work if a time switch or programmer has switched it off. The way to set and use your room thermostat is to find the lowest temperature setting that you are comfortable with, and then leave it alone to do its job. The best way to do this is to set the room thermostat to a low temperature – say 18ºC – and then turn it up by one degree each day until you are comfortable with the temperature. You won’t have to adjust the thermostat further. Any adjustment above this setting will waste energy and cost you more money.

Room thermostats need a free flow of air to sense the temperature, so they must not be covered by curtains or blocked by furniture.

dpstar Group is the sole distributor for Rainbow, Sunvic, and Ecostar thermostats.

Please send your inquiry to: info@dpstar.com.my.

STRIP HEATERS

dpstar is a manufacturer and one of the biggest supplier of strip heaters in Malaysia.

Strip heaters are used principally for convection-type air heating and clamp on installation. It is an excellent industrial heating product that can be easily controlled by using a temperature controller or a mechanical thermostat that can be installed on the surface you are heating. When selecting strip heaters two important factors must be considered: the proper sheath material for resisting any rusting and oxidizing inherent in the process environment and for withstanding the sheath temperature require.

Mounting holes are useful to mount the process heaters securely on almost any surface with terminal extending from the sheath for easy electrical connections. Many users also request lead wires that extend from one end that make the installation more flexible as the temperature control panel is easily adaptable to this configuration.

Temperatures as high as 250 Celsius can be reached and that allow for effective heat transfer. A fairly inexpensive way of heating surfaces or small areas, strip heaters are an excellent solution to meet any budget. Strip heaters are composed of a heating element, a protective sleeve or sheath, and mounting hardware. If strip heaters are used as a radiant heater, they have can have fins to maximize surface area and heat transfer to the air. Strip heaters can be clamped or bolted onto objects or solid surface contact heating over large areas and are primarily used in indoor applications.

dpstar also manufactures other industrial heating products i.e. immersion heaters, infrapara heaters, ceramic heaters and etc. Click here to view our products.

Industrial Heater

Types for Electric Heaters for Direct Heating

Direct Heating
dpstar  manufactures and supplies various types of industrial heaters.
Direct heating, as the name implies, is a heating method in which the heater is directly immersed into the medium to be heated (it can be liquid or gas, depending on the industrial process). This is the most efficient method of heating, as there is no thermal lag or heat transfer losses. Plus, the method is also considered as more energy efficient and precise than indirect heating because the heat generated in this process by the electric heater is immediately absorbed in the fluid. However, mounting styles and temperature control vary with the type of electric heater.

Indirect Heating
Indirect heating is based on the basic principle of heat transfer from the hotter medium to the colder one. The method does not use electric heaters directly. The fluid to be heated is usually stored in a heating tank, and external heat is applied. The method usually uses heating pipes and boilers to heat the fluid.

• Immersion Heaters

Immersion electric heaters consist of a mechanical thermostat and digital sensors to heat the fluid to the desired temperature. These heaters are called immersion heaters because the heating element is directly immersed into the fluid to be heated. However, the design of immersion heaters depends on the wattage rating and area of application.

• For small reservoirs, screw immersion heaters are used.
• For medium to large-sized tanks, flanged heaters are used.
• For tanks without openings, over-the-side immersion heaters are used.
• Circulation Heaters

Circulation heaters are also electric industrial heaters used to heat viscous fluids. The heating element in circulation heaters keeps on regulating, which facilitates for heat transfers through dense fluids. They are preferred over immersion heaters in applications with space limitations, as these heaters can be directly installed in the heating tank.

• Suction Heaters

The heavy fuel industry uses electric suction heaters to heat viscous oils and gases. These heaters consist of a flanged heating element immersed into the heating tank while the other end of the heater is open. The fluid pumped from the tank can be heated directly. These heaters eliminate the need of an additional storage tank.
Now that you now the various types of electric heaters used in industrial heating, keep technical factors and heating requirements in mind to choose the right type of industrial electric heater.

Call us to discuss how we can meet your individual needs.

HP: +6012-307 3907

Email: kennylim@dpstar.com.my

Please send your inquiry to: info@dpstar.com.my

Website: www.dpstar.com.my

dpstar Group of Companies Corporate Video

As the saying goes a picture tells a thousand words, this video will enable our customers/principal-suppliers/viewer to better understand with confidence dpstar group’s background, specialisation, range of products, brands, services, and expertise.

dpstar Group is a leading manufacturer of thermocouples (temperature sensors) and industrial heaters based in Malaysia. Our 25 years of expertise lies in complete factory/building automation and control components as well as process/hybrid control systems from project design up to testing, system integration, and commissioning. We have successfully built a strong reputation for electrical, instrumentation, and control systems and as a result expanded our foothold in Kuala Lumpur (KL), Petaling Jaya, Penang, Johor Bahru, Ipoh, Seremban, Melacca, Selangor, Kedah, Sabah, Sarawak through direct companies and ventured overseas in Asia through our partner companies in Thailand, Philippines, Singapore, Indonesia, and so on.

Float Switch/Level Switch

The purpose of a float or level switch is to detect and control the level of rises or falls of a liquid in a tank.
Most float switches are the type that just open or close a circuit as the level of liquid in a tank rises or falls. With the more common reed switch, the device will have two electrical contacts sealed in a glass casing. The two leads will be close within the housing, but they will not be touching. The housing with the glass leads will be mounted at a point in the tank to determine the liquid level that triggers the response. In the liquid, you then have a magnetic float. As the level of the liquid in the tank rises or falls, the float will come closer to the leads. When the float is in range, the leads become magnetized and then come together, completing the circuit. When the liquid level changes in a way that brings the float away from the electrical contacts, they separate and the circuit is broken.

An example would be a float that rises with the liquid to trigger a switch that turns on a pump. When the pump has removed enough of the liquid, it can then disengage the pump. Conversely, a float could be configured to float in liquid that needs to maintain a certain level. As the level drops, the float will eventually come in range of the switch. This could then trigger the opening of a valve to refill the tank to a predetermined level.

These are just a few of the more simple functions that a float switch can perform. Depending on the purpose and the design of the switch, they can be applied to much more complex tasks. Understanding the desired application of the switch will help to determine the right type of float switch that should be used and the configuration.
We at dpstar Manufacture and design various type of Maltec Float Switches or Maltec Level Switches.

Please send your enquiry to: info@dpstar.com.my.

Thermocouple vs RTD’s

The following chart indicates some of the advantages and disadvantages of RTD’s and thermocouples.

	THERMOCOUPLE	RTD’S
Accuracy	Limits of error wider than RTD	Limits of error smaller than thermocouples
Ruggedness	Excellent	Sensitive to strain, shock, and pressure
Temperature	-240° to 2300°C	-128°C to 800°C
Size	Can be as small as .01” sheath material, tip sensitive	Size limited to 1/16”, temperature sensitive for length of bulb
Drift	Should be checked periodically,	0.01 to 0.1°C per year, less drift than thermocouple
	higher than RTD’s
Resolution	Must resolve millivolts per degree, lower signal to noise ratio	Ohms per degree, much higher
		signal to noise ratio than thermocouple
Cold Junction Reference	Required	Not required
Lead wire	Must match lead wire calibration to thermocouple calibration	Can use copper lead wire for extension wire
Response	Can be made small enough for millisecond response time	Thermal mass restricts time to seconds or more
Cost	Low	Higher than thermocouples

dpstar is the leading manufacturer and supplier of Thermocouple and RTD’s in Malaysia and  South East Asia.

Please send your enquiry to: info@dpstar.com.my.

Immersion Heater: Simple Calculation

Electricity is measured in kilowatt hours (or kWh). A kWh is a unit of energy equivalent to one kW of power expended for one hour.In some cases, people heat their water with electricity – normally through the use of electric immersion heaters – that act like huge like kettles. We often get asked whether these are expensive to run, so the following should help you work that out for yourselves!

·         How many KW of electricity are needed to heat a hot water tank?
So the two bits of information you are going to need to help calculate this are the size of the tank measured in litres and the required temperature rise.
The required temperature rise (measured in centigrade) is calculated by taking the starting temp of your cold water from the hot water temperature required. For example if your water is 100C and you want to heat it up to 600C, then the temperature rise would be 500C.
The following formula can then be used to calculate the power (in kW) needed to heat a specific volume of water by a given temperature in 1 hour.

·         Volume of tank x 4 x temperature rise / 3412 = Power required
So if the tank is 125 litres and you want to take the water up to 650C from 100C, then it would simply be:
125 x 4 x 55 / 3412 = 8kW
This means that you would need 8kW of electricity to heat this volume of water up in 1 hour. If you wanted to heat it up in 30 mins you would need 16kW of power and so forth.

·         Immersion heaters are measured in kW
When you buy an immersion heaterit is given a kW rating, so for example 3kW or 6kW.
If you take the above example and have a 3kW immersion heater it would take about 2hrs 30min to heat the water (3kW each hour, so in two and a half hours that would give 7.5kW).

·         Cost of running an immersion heater
The cost of electricity is about 14 sen/kWh, which means that it would cost about 45 sen to run a 3kW immersion heater for an hour.
Normally though the immersion will turn on and off via the thermostat or a temperature controller so the amount of time they are on fluctuates, depending on the existing temperature of the water in the hot water tank.

dpstar Group is the largest manufacturer of Heaters and Thermocouples in Malaysia.
For further enquiries on immersion heater please visit:- www.dpstar.com.my and our engineer are ready to serve you.