output current whenever spring-loaded PUSH
T2, and T3 are connected in a delta configura-
TO INDICATE switch S1 is in depressed posi-
tion, as shown in the simplified schematic dia-
tion. With switch S1 depressed, load current
output voltage from the secondary windings of
R1 produces a small voltage drop which is pro-
T1, T2, and T3 is converted to a pulsating di-
portional to the current. Although the scale of
rect-current (dc) voltage by full-wave recti-
CURRENT meter M1 is marked to indicate
fiers CR1 through CR12. The dc pulses appear-
amperes, the meter is acutally a millivoltmeter
ing across resistors R2 and R3 are applied to
which measures the voltage across shunt R1.
B1 is connected across one of the primary
When PUSH TO INDICATE switch S1 is re-
windings of T2.
leased to the off position, the switch creates
a short circuit across R1 and M1. DC OUTPUT
lamp DS1 indicates the presence of dc power.
Overcurrent relay K1 provides protection if ex-
cessive current flows. Thermal switch S2 pro-
VOLTAGE meter M2 is connected across the
vides protection from excessive heat that may
output of the power supply and monitors the
output voltage. CURRENT meter M1 monitors
Power supply output circuit,
simplified schematic diagram.