GROUND RADIO BULLETIN NO. 37 - DECEMBER 12, 1951 COMMS. DEPT. L.A.D.
CIRCUIT BREAKERS
The Square D Circuit Breakers installed at most stations on the control racks, will sometimes develop an open circuit condition. This has been found in quite a few.cases to be due to fine dirt and grit penetrating inside the breaker.
When this occurs, the switch will fail to close the circuit when turned to the "on" position. The breaker can be repaired by opening the case after removing two screws at each end. Examination of the moving parts will show how the contacts operate, and the trouble will usually be caused by dirt increasing friction of the spring operated switch blades to the point where the spring cannot overcome this resistance to throw the switch blades. The binding can usually be overcome by assisting the movement with a small screw driver several times. After the breaker operation has been restored, or partially so, a small amount of light oil applied to the spring operated blade where the binding occurs will restore smooth and positive operation when the trouble is from this cause.
MERRY CHRISTMAS - HAPPY NEW YEAR
FELICES PASCUAS Y PROSPERO ANO NUEVO
FORM 9211—2107