Standard Oven shuts off during service

[fixbear]

Southbend on that range uses a thermopile instead of a thermo couple.  Therfore the pilot flame has to be on for it to be right.  This is the possibles;

 

I suggjest that you take a digital multimeter and check the output of the thermopile. Open it should be aproximatly 750 millivolts. Connected to the valve it needs to be above 450 millivolts. You will see it change as you adjust the pilot flame. 

 

What fuel is it on and if the original plate is not the same,  You may have the wrong orifice or pilot assembly.  I also highly recommend that you pressure test the gas pressure and regulator setting with a manometer.  Do you  see a normal pilot flame or does it soot or burn yellow at all.  . 

 

The other thing I have seen with them is that the pilot orifice and air intake get clogged with lint that reduces the heat for the thermopile.  It will start as tripping after long off periods and increase to tripping during use.  The radiant heat in the burner area tends to provide just enough extra heat to keep it lit during use, but after a long cooling period it trips out from low voltage.