Three Phase Thyristor Triggering Card – LZF-3
₹8,925
Prices are inclusive of Delivery Charges.
LZF-3 – Three Phase Zero Cross Over thyristor Triggering / SCR Firing Card for 2 leg or 3 leg control.
Please refer the Ordering Information table before placing your order.
Libratherm offers a three-phase SCR firing card model LZF-3 for switching power to three-phase operated resistive or inductive loads. This card was developed to replace the electro-mechanical contactor with an electronic solid-state switch built using silicon-controlled rectifiers (SCRs). When
the electrical load is operated through contactors – the AC cycle is switched ON or OFF at any point of 0 to 180degree phase angle; this may lead to the generation of arcing on the contacts and may generate harmonics, which may cause electromagnetic disturbance in the power lines and may
also cause the malfunctioning of other electronic instruments on the panel. The card featured here eliminates the generation of such harmonics because of the zero cross-over switching technique. No arcing or audible noise will be observed during the switching operations – since no mechanical switching contacts are involved in the solid-state device, the operation will be noiseless and silent.
LZF-3 accepts one standard linear signal of 4-20mA/0-5V/0-10V/Potentiometer or DC pulse/ potential free contact input from either temperature controller or PLC and generates three independent gate cathode triggering pulses (G1K1+G2K2) for 2 or 3 pairs of back-to-back connected SCRs. Hence, one can control a single 3-phase load in star or delta configuration (As shown in the DIAGRAM-2). The linear signal is pulse width modulated for burst fire to generate pulsating output with variable on/off duty cycle time of 2 to 30 seconds adjustable using an on- card potentiometer.
Key Features:
- Designed to fire 25 Amps to 1000 Amps SCR-SCR modules of Semikron, IXYS, IR, Proton, Hind Rectifier, Ruttonsha etc….
- 3 phase 2 leg or 3 phase 3 leg control versions
- Suitable for both two or 3-leg star/delta load configurations
- Auto / Manual operation.
- Accepts DC pulse / Contact or Linear Signal input (4-20) mA / (0-5)V / (0-10V.
- Pulse Width Modulated output proportional to the linear signal
- Healthy relay and Trip relay contacts
- Remote start/stop using potential free contact.
- Adjustable duty Cycle ON-OFF time.
- Operates on 230VAC Auxiliary supply.
Technical Specification
| Parameters | Description |
|---|---|
| Item | SCR Firing Card with ZERO Cross burst firing technique for a 3-phase resistive or inductive load |
| Models | LZF-3 |
| Control Input | 12 to 36VDC pulse or potential free contact or |
| 4-20mA/0-5V/0-10V – user selectable using DIP switch. | |
| Triggering Pulses | Gate/ Cathode pulses - Optically isolated from the Input – suitable to fire 25A to 500A back-to-back connected SCRs. |
| G1K1+G2K2 X 3 = 12 pulses. | |
| Load Configuration | 3-phase star or delta-connected load. (As shown below in the load configuration DIAGRAM-1) |
| Cycle Time | 2 to 20 seconds adjustable duty cycle |
| Supply Voltage | 230VAC +/-10%, single phase, 50/60Hz. |
| Output Line Voltage | 110VAC/230VAC/415VAC Or any other lower line voltage from the step-down transformer up to 50VAC – on request |
| Operating /Storage Conditions | 0 to 60oC @ 90% RH (Non-condensing environment) |
| Mounting | Screw mounted on the base plate. |
| Size (H x W x D) | 165 x 115 x 65 mm. |
| Certification | CE certified (Low Voltage Directives – 2014/35/EU and EMC Directives – 2014/30/EU) |
Ordering Information
| Model | Product Description | Part No. |
|---|---|---|
| LZF-3 | 3-phase zero cross-over burst-firing SCR triggering card for two-leg or three-leg control of Resistive/Inductive Load | 2201 |
