Elmo 16-CL - Page 45

Immediately after S-5 is switched on, most of current flow through
R22 (Route (l)). 6
At this time, voltage applied to Magnet Clutch (Voo) is about J2V.
(Voo is calculated as Voo = Vcc x =——).
Ro + R22
After S -5 is switched on, C29 is charged with the current through
R 20 and when the terminal voltage of C29 exceeds the Zener Voltage
of ZD1, current starts to flow through ZD1, Trl and Tr2.
The current, which flows through R22 during the delay time, turns
to flow through Tr2.
In the end, all current flow through Tr 2 as the Equivalent Resistance
of Tr2 comes to nearly zero.
At this time, Voo is calculated as Voo = 37 x — *^270 = 37V,
i.e., Vcc of 37V is supplied to Magnet Clutch.
16-CL is so designed that it takes about 3-4 seconds to increase
Voo from 12V to 37V (Delay Time).