- Designed to fire 25 Amps to 1000 Amps SCR-SCR modules of Semikron, IXYS, IR, Eupac,Hind Rectifier and Ruttonsha or any other make.
- Single phase / 2 phase / 3 phase versions.
- Suitable for both star or delta or rectifier load configurations.
- Suitable for single phase or three phase Heaters, Transformers, DC rectifiers
- Soft starter for 3 phase AC induction motor. (Our card MSST-15)
- Auto / Manual operation.
- Accepts (4-20)mA / (0-5)VDC / (0-10)VDC control inputs
- Soft start for smooth control.
- Adjustable power and current limit.
Libratherm offers SCR triggering cards model LTC-12, LTC-13 and LTC-15 and LTC-18 , which are designed to fire or trigger back to back connected SCRs using synchronized phase angle control technique. The card accepts analogue control signals of (0-5)/(0-10)VDC or (4-20)mA and provides proportional gate/cathode triggering pulses G1K1 G2K2. These pulses can be used to trigger back-to-back connected SCRs upto 1000Amps with gate current upto 300mA. The card also provides built in regulated 5VDC supply to connect external potentiometer to manually control the SCR firing. The on card ramp up and ramp down settings allows gradual rise and fall of the voltage levels across the load.
Many times it is required to limit the current flowing through the load. Such current limiting feature is available in LTC-13 – for single phase and two phase load. Whereas for 3 phase load, common three phase current limiting is achieved by LTC-18 card. The load current or Line current feedback is derived from the external CTs. This feature is useful for transformer load or inductive loads or for heating elements like Silicone Carbide and Molybdenum Disilicide, which exhibits significant change of resistance with increase in temperature. This feature will restrict the maximum load current to the value set using the on card current limit (CL) potentiometer. On sudden increase in the current the current trip feature will over-ride the current limit feature and the firing of the thyristor will stop instantly. The trip contacts are available on the terminals.
These cards are designed for heating control applications to control the single phase, two phase and three phase AC power across the heating coils to control the star or delta connected transformer loads. LTC-15-3 can also be used for Induction Motor soft start application to gradually control the speed of 3 phase AC induction motor our model MSST-18.
These cards can also be used for half wave, full wave or bridge rectifiers using SCR-DIODE or SCR-SCR Bridge, where the rectified DC output can be gradually varied to the desired level using the control signal or the potentiometer.