What is an SCR Controller?

SCR Controller (Thyristor Controller) is a specialised electronic device used to regulate Voltage and/or Current into different types of loads/processes including; Resitive or Inductive Heating Elements, Electrolysers, Chlorinators, Electroplating, Welding, Drives applications. 

SCR Controllers control an ac switch to regulate the output by turning on and off a simple AC switch. 

What is an AC Switch?

An AC switch is simply two back to back paried SCR's as shown below. 

The type of load determines which type of controller to be used for each. The process will also determine what options are required. 

A) There are two main control modes for SCR Controllers. The different modes have fundamentally different ways of swithcing the power to the load:

Phase Angle Control (VAR)

There are variuous options to be considered depending on the application. The mandatory options are listed below:

Burst Control (TAKT)

The mandatory options are listed below:

 

B) Different forms of SCR Controllers

There are various forms of what are reffered to as "SCR Controllers"

1) Fully Optioned SCR Controller (as shown above)

See Thyro Series . These are fully trunkey and reayd to install. normally with integrated fuses. and only require an external contactor to Isolate the circuit. 

Note:Can be used for all SCR Control Applications. Can have closed loop feedback and operate in Voltage, Current, or Power Limit/Control modes

2) SSR based SCR Controllers.

See PMP2450WP or other similar integrated SSR With SCR outputs. These Controller look the same as a normal SSR howver they have they will accept an anlogue input for priportional control of the AC switch output. Note that some very old SSR may use old Triac technology, so be careful to ensure you do have SCR output which is much more rbust with more accurate control. You may also need to provide heat sink much like with SSR.

Note:Can be used only for resitive loads. (no closed feedback option)

3) SCR Trigger Modules

Such as FKPC-240-CE. These modules are designed for use with an external SCR stack which is a back to back pair of SCR's with heat sink.

 Note:Can be used only for resitive loads. (no closed feedback option)

Should you ave further questions, feel free to ask the friendly team at Fastron Electronics