08-05-2012, 04:30 PM
OPEN CIRCUIT TEST AND LOAD TEST ON SEPARATELY EXCITED
DC GENERATOR
[attachment=21593]
PROCEDURE
Open circuit test
• Connections are given as per the circuit diagram.
• The Prime Mover is started with the help of the three point starter and it is made to run at rated
speed when the Generator is disconnected from the load by DPST switch.
• By varying the Generator field rheostat gradually, the Open Circuit Voltage (Eo) and
corresponding Field Current (If) are tabulated upto 150 % of Rated Voltage of Generator.
• The motor is switched off by using the DPIC switch after bringing all the rheostats to initial
position.
Load test
• Connections are given as per the circuit diagram.
• The Prime Mover is started with the help of the three point starter and it is made to run at rated
speed when the Generator is disconnected from the load by DPST switch..
• By varying the Generator field rheostat gradually, the Rated Voltage (Eg) is obtained.
• The Ammeter and Voltmeter readings are observed at no load condition.
• The Ammeter and Voltmeter readings are observed for different loads up to the rated current by
closing the DPST switch..
• After tabulating all the readings the load is brought to initial position.
• The motor is switched off using the DPIC switch after bringing all the rheostats to initial position.
GRAPH
The graph drawn as
• Open Circuit Voltage Vs Field Current
• Load Voltage Vs Load Current
DC GENERATOR
[attachment=21593]
PROCEDURE
Open circuit test
• Connections are given as per the circuit diagram.
• The Prime Mover is started with the help of the three point starter and it is made to run at rated
speed when the Generator is disconnected from the load by DPST switch.
• By varying the Generator field rheostat gradually, the Open Circuit Voltage (Eo) and
corresponding Field Current (If) are tabulated upto 150 % of Rated Voltage of Generator.
• The motor is switched off by using the DPIC switch after bringing all the rheostats to initial
position.
Load test
• Connections are given as per the circuit diagram.
• The Prime Mover is started with the help of the three point starter and it is made to run at rated
speed when the Generator is disconnected from the load by DPST switch..
• By varying the Generator field rheostat gradually, the Rated Voltage (Eg) is obtained.
• The Ammeter and Voltmeter readings are observed at no load condition.
• The Ammeter and Voltmeter readings are observed for different loads up to the rated current by
closing the DPST switch..
• After tabulating all the readings the load is brought to initial position.
• The motor is switched off using the DPIC switch after bringing all the rheostats to initial position.
GRAPH
The graph drawn as
• Open Circuit Voltage Vs Field Current
• Load Voltage Vs Load Current