Buyers can get in touch with us for obtaining the Three Phase Without Neutral Thyristor Power Controllers at nominal rates. Our Power Controllers are widely demanded in various industries across the world. We are an illustrious Manufacturer, Exporter & Supplier from Delhi, India and are capable of delivering Three Phase Without Neutral Thyristor Power Controllers within the promised time.
- Soft start – bake out feature prevents moisture at start up
- Current Limit , Phase Loss Trip, Over temperature Trip
- Microprocessor Digital Programmable Thyristor Power Controller with Percentage
- Display. Program setting of Current Limit, Soft start etc by front keys
- Single Phase – 25 , 34, 59, 70, 90, 150, 200 , 250, 300 Amperes
- Double Phase – 25 , 34, 59, 70, 90, 150, 200 , 250, 300 Amperes
- Three Phase Star/Delta- 35, 50, 70, 90, 150, 200, 250, 300, 350, 400 Ampers
- Three Phase Star with Neutral - 35, 50, 70, 90, 150, 200, 250, 300, 350, 400 Amperes .
Dydac Controls Thyristor SCR Power Controllers some typical applications :
- Large tank heating and mechanical relay replacement.
- Thermoforming, textiles, industrial furnaces and ovens, extruders, kilns, chemical process heating, fast water heat.
- Paper and pulp drying, packaging machines, pharmaceutical processes, infrared ovens and dryers.
- High-temperature ovens and furnaces, kilns, glass, ceramics & hightemperature alloys.
- High-speed paper and ink dryers, high temperature IR heating, high temperature materials processing.
- Primary of transformer-coupled loads.
- Phase angle proportional control. No temperature or power cycling
- I2T Rectifier fuses standard
- Isolated SCR's
- Integrated thermal/mechanical design saves panel space
- Voltage protection - MOV capacitance
- 10 to 400 Ampere current ratings. Other Ratings Over 400 Amps Possible.
- Easy to install, test, service
- The Dydac Thyristor Power Controller is a heavy duty, fully Digital or Analog one, two or three phase power control unit for controlling the voltage applied to loads such as heating elements, thus, allowing temperature control while eliminating contactor switching and over/under heating.
- The first in a series of Digital or Analog Thyristor ( SCR ) Power Controllers incorporating protection functions.
Built in switching methods are :
- Phase Control Firing
- Zero Crossing Firing
Range : 15 A - 400 A , 220-1200V
Advantages at a glance :
- Fully digital Thyristor
- Analog Thyristor
- Phase Control and Zero Crossing
- Current: 15 – 400 A (consult us when higher ratings are needed)
- Voltage: 230- 500 V 50/60Hz
- Cooling Method: Forced air
- Ambient. Temp: 0 - 50°C
- Continuous Duty
- One, Two or Three controlled phases
- Input, 4-20mA or 0-20mA, 0-10VDC
- Digital display
- Over Current
- Over Temperature
Connection types :
- Single Phase
- Double Phase
- Three Phase Star or Delta Connection
- Three Phase Star with Neutral
Protection functions :
- Under & Over current
- Phase loss * Shorted SCR
- Heat sink over temperature Trip & Alarm
- Internal failure
- The SCR control can deliver electrical power to heaters in several ways - phase angle
- fired, zero voltage switched and on/off control.
Power Calculation : When selecting the correct sized SCR power controller, rate the SCR for at least 110% of the heater load. Heaters and power lines have tolerances that can swing on any given day or location.
Single Phase :
- Watts÷ Volts÷1.73 = Amps - Example: 18,000W ÷ 415V÷1.73 = 75A
- Amps X Volts÷1.73 = Watts
Phase Angle Fired : These controls proportionally turn on a percentage of each power line half cycle. This gives smooth, infinitely variable application of power to the heaters. Imagine a light dimmer and how it provides power to a light bulb. This method will provide the most precise control of heaters. Phase angle fired SCR’s will respond the fastest to load change and provide maximum heater life. It is the most precise method of control. Phase angle firing can increase heater life up to seven times depending on heater type. Phase angle firing also allows options such as soft start, voltage limit and current limit. These options are not available with any other means of control.
Equipment manufacturers and maintenance engineers need a reliable, flexible approach to controlling electric-heating processes in today’s competitive, cost-conscious, industrial environment. And making the right choices up front is vitally important. Let us help you Understand SCR Power Controls , compare Power Control Methods to make the right selection, and determine the type of Electrical enclosure you need.
Understanding SCR Power Controls : When selecting SCR Power Controls it is important to have a basic understanding of how SCRs work. This will help you select the right SCR for your application.
How SCR Power Controls Work : A silicon controlled rectifier (SCR) is a solid state switching device which can provide fast, infinitely variable proportional control of electric power. Not only does this give maximum control of your heat process, but it can extend heater life many times over other control methods. Since the SCR is solid state, it can cycle on and off over a billion times, if properly used.
The advantages of SCR Controls over other temperature control methods :
- Improved response time.
- Closer process control.
- Extended heater life.
- Reduced maintenance costs.
- Silent operation. No arcing and sparking.
- Reduced peak power consumption.
- Remember, a heating element is made of wire in most cases. If you use a mechanical relay to turn on your heater, it will cycle on or off within 30 seconds or longer. The heater will expand and contract, getting more and more brittle each time. This is called thermal shock. Temperature overshoot may also occur. Relays also arc, spark and will burn out on a regular basis. Mercury displacement relays can cycle from 3-15 seconds. While it controls better than a mechanical contractor, overshoot and thermal shock will still occur. If cycled too fast, Mercury relays can overheat and explode causing Haz-Mat problems
- Comparing Different Methods of Power Control : There are several methods commonly used to control power to electric heaters. Although some may seem “cheap and easy,” the total costs are not always considered.
- Mechanical Relays/ Contractors : The up front cost for a simple relay is low on low power levels. As the power level goes up, the price rises. Since the mechanical relays will get dirty, arc and burn out, the relay has to be replaced every so many cycles. The labor cost associated with this is often overlooked. Due to the slow cycle time inherent for mechanical relays (30 seconds minimum) control is poor, heated process may be damaged and heater life is shortened due to thermal shock.
- Mercury Displacement Relays : (MDR) The up front cost of a mercury displacement relay, or MDR, is low at low power. The MDR can cycle faster than a mechanical relay, and will not burn out as quickly. MDR’s do have to be mounted in one direction. However, the MDR will explode if overheated due to cycling too fast, or if overpowered. This results in a Haz-Mat problem. Control is still poor compared with solid state devices. The heater is still receiving full line voltage for several seconds at a time.
- Solid State Relays : (SSR) The costs of low power Solid State Relays (SSRs), is also low. However, there are several cost factors forgotten about with SSRs. Common to all solid state devices, they generate heat and have to have heat sinks. Also, SSRs generate more heat than SCRs due to their packaging, and come without lugs that make a solid electrical connection for higher power levels. The MOVs and fuses needed for protection against electrical shorts and spikes have to be customer installed. Again, this is a hidden cost. Finally, when looking at the SSR data, you must alwaysDerate the Device. Manufacturers of SSRs have derating curves published in their catalogs. However, please note that all SSRs are rated for the name plate power rating at 25ºC/77ºF ambient temperature. So a 50 Amp SSR is not good for 50 Amps if the temperature in the enclosure or work area is above 25ºC/77ºF (how hot is your facility in July?). The single surge current and voltage spike ratings are not as strong as an SCR. The SSR can cycle once a second and deliver better performance to both process and heaters than mechanical means. However, SSRs can only turn cycles on or off.
- Silicon Controlled Rectifiers : (SCR) The costs of Silicon Controlled Rectifier (SCR) Controls, is higher at low power, but level out with other methods at mid to high power. All Dydac SCRs come equipped with proper heat sinks, semi-conductor fuses and power lugs installed as an integrated package. With standard MOVs and DV/DT protection for line noise and voltage spikes, an SCR control can operate for decades. There is no routine maintenance to carry out. The level of control that can be achieved with a SCR is unattainable with any other devices. Phase angle firing and zero voltage switched control offers 0.08 second response times on 60Hz power lines. Heater life can be extended by 7 times. Power to heaters is infinitely variable. Soft Start, Current Limit and Voltage Limit Options give advantages for controlling heaters. Soft Start allows the use of high inrush heaters. Current Limit gives control of high temperature elements for furnaces. Voltage Limit prevents temperature overshoot and extends heater life. Peak power is reduced, saving operators utility costs.
- Protecting Your SCR Controls from Failure : Heat is the main enemy associated with SCR Control Failure. In fact, heat is the main enemy of all solid state devices. Almost all semiconductors, including transistors, IC/s and thyristors (SCRs and TRIACs) will be destroyed at an internal junction temperature of 125ºC. Diodes can take a higher internal junction temperature (130-200ºC). This is one reason Dydac Controls uses back to back SCR and SCR-Diode combinations whenever possible. Heat is generated by voltage drops across a power device (SCR/TRIAC). This drop can be anywhere between 1 and 2 volts depending on the device. The more current (amps) put through the device, the higher the watts the device will dissipate in the form of heat. This heat must be removed or the device will fail. All Dydac SCR Controls are designed to run at full rated amperage at 50ºC / 122ºF ambient.Remember, you will need air inlet and outlet holes with fan cooling. Finally, plastic enclosures act as an insulator. You will most likely destroy an SCR control if you install it inside a plastic box. The only reliable way to use a plastic enclosure is to have a “thru-hole mounting” style heat sink, with the heat sink’s cooling fans outside of the box.