[marcelo2112]

Hello everyone, I am repairing a curtis 1244, I see that it has an H bridge to feed the motor rotor.
If the positive of the battery goes directly to the motor, why does it require a bridge h? Greetings and thanks.

 

[marcelo2112]

The Curtis 1244 SepEx uses a full (H) bridge for the field (stator) and a half bridge for the armature (rotor).

major

Perfect, but why half a bridge in the rotor? To brake? I am changing mosfet and wanted to save me some of the half bridge high side, will it work? Thank you.

 

[marcelo2112]

Thank you. Then I have to change all the mosfet.

 

[marcelo2112]

I ask the experts, what is the circuit that closes the main contactor? I have the code 3.4, change all the lm339 but I do not understand the circuit that activates the mosfet, where does the signal that activates it come from?