|STUDY OF SCR CHARACTERISTICS Or (Mosfet Characteristics) (LGS PE-1)
The set up comes in to parts with provision for high voltage variable power supply (0 to 500 volts), 0 to 10 volts with voltmeter and provision for gate current measurement, anode current measurement in the range of 0 to 10 mA.
The part (A) houses variable power supply and part B provides facility to connect various SCR or MOSFET,diac,triac,IGBT along with load. Various characteristics of the device with measurement of latching current, holding current for SCR can be performed.
|STUDY OF SCR FIRING CIRCUITS: (LGS PE-2)
Study of SCR firing circuits can be done with the help of five methods namely
i) Basic D.C. firing circuit.
ii) Resistance firing circuit.
iii) R-C phase shift-firing circuit.
iv) Ramp and pedestal with anti parallel connected SCRs circuit.
Scope of supply:
This set up having top anodized plate, with printed circuit diagrams, includes ammeter & voltmeter for load current & voltage measurement.
1. 61cm(L) 40cm W), 10cm(H)
2. Panel provision
3. Facility for observation of waveforms on C.R.O.
4. Provision for varying firing angle of SCRs.
5. Load control facility.
6. Appropriate test points are provided on panel.
|JONES CHOPPER (LGS PE-3)
30 V d.c. 1A fixed power supply for the chopper and d.c. Voltage is chopped down by main thyristor and commutating thyristor for variation of output from voltage of 5 to 25 volts b varying the on time control and frequency control of the chopping frequency circuit of the main thyristor. Optional analog voltmeter provided for measurement of output voltage. Appropriate test points provided. Size: 52 * 31*10cm (L*B*H)
|MORGAN’S CHOPPER (LGS PE-4)
A fixed d.c. Voltage of 30 volts provided for the input of chopper and the same is chopped down to vary from 5 to 25 volts by a single thyristor and resonating L-C circuit. Variable load facility provided. The frequency of chopping also can be varied. Waveforms can be observed with the test points provided on the panel. It is a self-contained unit. Panel size:52*31*10 CM.(L*B*H)
|SERIES INVERTER (LGS PE-5)
D.C. unregulated voltage provided for inverter and frequency control potentiometer to vary the firing frequency and the output frequency of series inverter in the range 30Hz to 60 Hz. 25 watt, 230 V output. Panel size: 61*40*10 cm. Anodized top plate with schematic diagram neatly labeled with appropriate test points 8 Amp. 600V SCR are used.
|PARALLEL INVERTER. (LGS PE - 6)
D.C. unregulated voltage provided for inverter, Mcmurray Bedford type inverter with fixed frequency provided. Inverted output stepped up to drive 2No.230 volt 15W lamps at 50 Hz.
Size: 61*40*10 cm.
|CHOPPER MOTOR CONTROLLER.(LGS PE-7)
This is a d.c. Chopper circuit for getting a variable D.C. Voltage by using on time control and frequency control to feed a 110V load. Circuit demonstrates the use of chopper circuit, Ammeter, voltmeter and test points are provided. JONE’S CHOPPER PRINCIPLE USED FOR OPERATION.
Scope of supply
¼ HP, 110 Volt, D.C. Series motor mounted on rigid base, 360(L)*250(W)*250(H) mm dimension aprox, BOX TYPE PANEL SUPPLIED Lamp load optional. Anodized & printed alluminium plate on the front panel.
|SINGLE PHASE CYCLOCONVERTER. (LGS PE - 8)
600 (L)*500(W)*100(H) mm approx. 30-0-30 volts a.c. at 50 Hz provides input for a cycloconverter thyristorised bridge from which output is obtained at 25 Hz, 16.66 Hz and 12.5 Hz thus demonstrating the frequency reduction to ½,1/3 and ¼ of the a.c. mains frequency using digital logic circuits. Output of digital logic circuits is coupled to the thyristor gates by using optoisolators. All the waveforms can be observed with the help of the test points.
Scope of Supply
Top panel is appropriately labeled & test points are marked. Detailed instruction manual with circuit diagram and theoretical explanation for the students. Panel is mounted on rigid base.
|SINGLE PHASES HALF-CONTROLLED CONVERTER. (LGS PE-9)
500(L)*400(W)*220(H) mm. approx. Panel provision: Half-controlled converter with facility for connecting D.C. motor. This is a 230 volt mains operated converter suitable for 1 HP 230 volts D.C. motor. The circuit makes provision for 230 volt field supply also. All the test points fpr typical triggering circuit can be observed with the help of C.R.O. The system also includes a soft start facility alongwith ammeter and voltmeter. The set up is provided with isolation transformer for C.R.O. protections and lamp bank.
Scope of supply:
Front panel of the equipment is having anodized and printed of aluminium. 0 to 5 Amp. Ammeter and 0-250 volt, Voltmeter 1 HP, 230 volt D.C. Shunt Motor is optional at extra cost. Detailed instruction manual with circuit diagrams & theory.
|SINGLE PHASE FULLY CONTROLLED CONVERTER.(LGS PE-10)
This is a 230-volt mains operated converter suitable for 1 HP 230 volts D.C. motor. The circuit makes provision for 230 volt field supply also. All the test points fpr typical triggering circuit can be observed with the help of C.R.O. The system also includes a soft start facility alongwith ammeter and voltmeter. Lamp load and Choke/No Choke facility provided. Panel includes 0-5 amp ammeter and 0-250 volt d.c. Voltmeter also. OPTIONAL D C MOTOR 1 HP CAPACITY.
|THREE PHASE FULLY CONTROLLED CONVERTER. (LGS PE-11)
Panel : Box type
Panel Dimensions : 500(L) *400(H)*300(W) mm approx.
Panel provisions : 0-3 amp. Ammeter for load Current Measurement.
0-230 volt D.C. Voltmeter for output D.C. voltage.
1 HP motor is optional at extra cost. Input 440 volts 3 phase, 50 Hz. 4 wire is stepped down with the help of 6 no. of transformers to form a 150 volt 6 phase system with current capacity of 4 amps. The system includes elaborate triggering circuit arrangement for a six thyristor fully controlled bridge converter with various test points and soft start facility and ammeter and voltmeter. 1 H.P. 230 volt D.C. motor can be driven from the output of this fully controlled converter.