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Introduction to Industrial Automation
automation circuit is equivalent to the one for the operation of an electric motor with a reverse
option. Instead of the two relays for changing the phase connections, in this case, we have the two
equivalent solenoids of the electro-valve that also should never be activated at the same time.
When an electro-pneumatic automation includes a large number (greater than three) of cyl-
inders, as well as the desired operation (which involves a complex combination of extension and
(a)
Pneumatic
circuit and equipment
Storage
a
b
Flow
control valve
Air compressor
N
C
R
C
START
STOP
d
1
C
Up
Down
d
2
a
b
d
1
d
2
Air
compressor
d
1
d
2
(b)
Automation
circuit
Figure 5.19 A light-object elevator with a double-acting cylinder, manual control of its piston
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