DG self starter motor and Dynamo

[sudhakar]

Sir,
I'm checking 500kva DG set.
In starting system battery negative lead connected to self starter motor terminal. Battery positive lead connected to solenoid and solenoid another end connected to self starter motor body.solenoid coil terminal one end connected to self starter motor negative another end connected to ignition button.how the self starter motor work ?
Battery positive end connected to self starter motor body, through solenoid.why earth fault not affecting the circuit?
Then Dynamo have three leads how to understand?

 

[duke37]

"Battery positive end connected to self starter motor body,"

I think you have the circuit wrong.
Normally, with recent equipment, the battery negative is connected to the chassis which the starter motor is bolted to.
The battery positive goes to the solenoid which has two fat connectors. The output fron the solenoid goes to the motor. There will be a smaller connector on the solenoid to activate the coil, this is connected to battery + when the button is pressed. The solenoid needs to be bolted to chassis to complete the activation circuit.

Dynamos that I have seen, use the body for one connection and a big terminal for the supply output. The smaller terminal is the field winding which is controlled by a box which sets the output voltage independant of rotation speed and may also limit the output current.

A dynamo can output either polarity and starts up with the last polarity. If the dynamo has not been used for a long time, then flash the field with the right polarity. You do not want the dynamo to try inputting negative to the battery positive.

 

[kellys_eye]

Dynamo??? When was the DG made.... 1850?

Sure it's not an ALTERNATOR? Two thin wires, one big fat wire?

Can you post pictures of the unit(s)?

 

[sudhakar]

"Battery positive end connected to self starter motor body,"

I think you have the circuit wrong.
Normally, with recent equipment, the battery negative is connected to the chassis which the starter motor is bolted to.
The battery positive goes to the solenoid which has two fat connectors. The output fron the solenoid goes to the motor. There will be a smaller connector on the solenoid to activate the coil, this is connected to battery + when the button is pressed. The solenoid needs to be bolted to chassis to complete the activation circuit.

Dynamos that I have seen, use the body for one connection and a big terminal for the supply output. The smaller terminal is the field winding which is controlled by a box which sets the output voltage independant of rotation speed and may also limit the output current.

A dynamo can output either polarity and starts up with the last polarity. If the dynamo has not been used for a long time, then flash the field with the right polarity. You do not want the dynamo to try inputting negative to the battery positive.

Thank you

"Battery positive end connected to self starter motor body,"

I think you have the circuit wrong.
Normally, with recent equipment, the battery negative is connected to the chassis which the starter motor is bolted to.
The battery positive goes to the solenoid which has two fat connectors. The output fron the solenoid goes to the motor. There will be a smaller connector on the solenoid to activate the coil, this is connected to battery + when the button is pressed. The solenoid needs to be bolted to chassis to complete the activation circuit.

Dynamos that I have seen, use the body for one connection and a big terminal for the supply output. The smaller terminal is the field winding which is controlled by a box which sets the output voltage independant of rotation speed and may also limit the output current.

A dynamo can output either polarity and starts up with the last polarity. If the dynamo has not been used for a long time, then flash the field with the right polarity. You do not want the dynamo to try inputting negative to the battery positive.

Thank you

 

[Kiwi]

Did you get this to work?

If not, please post photos of starter and dynamo wiring connections etc.