<s>
Automation	B-Application
Master	I-Application
is	O
an	O
open	B-Application
source	I-Application
community	O
maintained	O
project	O
.	O
</s>
<s>
Automation	B-Application
Master	I-Application
was	O
created	O
to	O
assist	O
in	O
the	O
design	O
,	O
implementation	O
and	O
operation	O
of	O
an	O
automated	O
system	O
.	O
</s>
<s>
Traditional	O
testing	O
techniques	O
required	O
staging	O
as	O
much	O
of	O
the	O
equipment	O
as	O
practical	O
in	O
the	O
laboratory	O
,	O
and	O
wiring	O
up	O
a	O
simulator	O
panel	O
containing	O
switches	O
and	O
indicator	O
lights	O
to	O
all	O
of	O
the	O
I/O	B-Architecture
modules	I-Architecture
on	O
the	O
PLC	B-Architecture
.	O
</s>
<s>
PLC	B-Architecture
software	O
would	O
be	O
tested	O
by	O
sequencing	O
the	O
toggle	O
switches	O
to	O
input	O
the	O
electrical	O
signals	O
to	O
the	O
input	O
cards	O
on	O
the	O
PLC	B-Architecture
,	O
and	O
then	O
observing	O
the	O
response	O
by	O
software	O
on	O
the	O
indicator	O
lights	O
and	O
operator	O
consoles	O
.	O
</s>
<s>
Real	O
time	O
simulators	O
such	O
as	O
Automation	B-Application
Master	I-Application
are	O
PC	O
based	O
software	O
packages	O
,	O
which	O
utilize	O
a	O
model	O
to	O
mimic	O
the	O
automated	O
system	O
's	O
reaction	O
to	O
the	O
control	O
software	O
.	O
</s>
<s>
Max	O
Hitchens	O
and	O
George	O
Rote	O
began	O
working	O
on	O
Industrial	O
Automation	B-Application
projects	O
in	O
the	O
late	O
1970s	O
.	O
</s>
<s>
The	O
RTCS	O
was	O
a	O
custom	O
system	O
with	O
3	O
single-board	B-Device
computers	I-Device
.	O
</s>
<s>
Along	O
this	O
time	O
the	O
IBM	B-Device
PC	I-Device
was	O
introduced	O
and	O
it	O
was	O
used	O
to	O
build	O
the	O
database	O
necessary	O
for	O
the	O
simulator	O
.	O
</s>
<s>
Well	O
almost	O
,	O
the	O
PC	O
did	O
not	O
have	O
enough	O
power	O
to	O
meet	O
the	O
real	B-General_Concept
time	I-General_Concept
computing	I-General_Concept
which	O
the	O
RTCS	O
required	O
.	O
</s>
<s>
As	O
the	O
8088	B-Device
PC	O
metamorphosed	O
into	O
the	O
80286	B-General_Concept
,	O
customers	O
were	O
increasingly	O
reluctant	O
to	O
spend	O
thousands	O
of	O
dollars	O
on	O
a	O
custom	O
piece	O
of	O
computer	O
gear	O
.	O
</s>
<s>
By	O
the	O
time	O
the	O
80386	B-General_Concept
personal	O
computers	O
came	O
out	O
,	O
the	O
RTCS	O
ceased	O
to	O
have	O
a	O
market	O
.	O
</s>
<s>
Fortunately	O
,	O
the	O
80386	B-General_Concept
and	O
subsequently	O
the	O
80486	B-General_Concept
had	O
enough	O
power	O
to	O
run	O
the	O
simulation	O
in	O
real	O
time	O
and	O
Automation	B-Application
Master	I-Application
was	O
born	O
.	O
</s>
<s>
By	O
this	O
time	O
,	O
Automation	B-Application
Master	I-Application
embodied	O
many	O
thousands	O
of	O
hours	O
of	O
development	O
and	O
use	O
.	O
</s>
<s>
Automation	B-Application
Master	I-Application
languished	O
until	O
2013	O
when	O
Max	O
Hitchens	O
decided	O
to	O
create	O
an	O
open	B-Application
source	I-Application
project	O
and	O
release	O
it	O
into	O
the	O
public	O
domain	O
.	O
</s>
<s>
Automation	B-Application
Master	I-Application
is	O
a	O
comprehensive	O
modeling	O
and	O
simulation	O
software	O
package	O
designed	O
specifically	O
for	O
design	O
,	O
implementation	O
and	O
operation	O
of	O
factory/warehouse	B-Application
automation	I-Application
.	O
</s>
<s>
Automation	B-Application
Master	I-Application
can	O
also	O
be	O
used	O
throughout	O
the	O
life	O
cycle	O
of	O
an	O
automated	O
factory	O
,	O
from	O
the	O
design	O
phase	O
,	O
through	O
the	O
implementation	O
phase	O
,	O
into	O
actual	O
production	O
.	O
</s>
<s>
An	O
automation	B-Application
project	O
is	O
a	O
cycle	O
of	O
activities	O
.	O
</s>
<s>
Automation	B-Application
Master	I-Application
is	O
used	O
for	O
software	O
quality	O
control	O
during	O
the	O
implementation	O
phase	O
.	O
</s>
<s>
The	O
real	O
time	O
simulator	O
may	O
be	O
connected	O
directly	O
to	O
the	O
automated	O
system	O
's	O
programmable	B-Architecture
controllers	I-Architecture
and	O
computers	O
.	O
</s>
<s>
Automation	B-Application
Master	I-Application
connects	O
to	O
the	O
Control	O
System/PLC	O
and	O
emulates	O
the	O
real	O
world	O
I/O	O
by	O
reading	O
and	O
writing	O
the	O
PLC	B-Architecture
's	O
internal	O
I/O	O
images	O
.	O
</s>
<s>
The	O
simulator	O
can	O
receive	O
the	O
Control	O
System/PLC	O
'	O
s	O
outputs	O
,	O
and	O
respond	O
with	O
the	O
inputs	O
in	O
real	O
time	O
without	O
the	O
need	O
for	O
any	O
hard-wired	O
physical	O
I/O	O
.	O
</s>
<s>
A	O
simulator	O
emulates	O
the	O
real	O
time	O
response	O
to	O
the	O
Control	O
System/PLC	O
actions	O
based	O
upon	O
a	O
model	O
which	O
duplicates	O
the	O
operation	O
of	O
the	O
automated	O
system	O
.	O
</s>
<s>
For	O
example	O
,	O
if	O
the	O
Control	O
System/PLC	O
sets	O
a	O
digital	O
output	O
to	O
start	O
a	O
motor	O
to	O
raise	O
a	O
door	O
,	O
the	O
model	O
,	O
within	O
milliseconds	O
,	O
provides	O
the	O
Control	O
System/PLC	O
with	O
an	O
auxiliary	O
contact	O
closure	O
to	O
indicate	O
that	O
the	O
motor	O
has	O
been	O
started	O
.	O
</s>
<s>
As	O
long	O
as	O
,	O
the	O
Control	O
System/PLC	O
keeps	O
on	O
the	O
output	O
signal	O
which	O
raises	O
the	O
door	O
,	O
the	O
door	O
in	O
the	O
model	O
continues	O
to	O
rise	O
.	O
</s>
<s>
When	O
the	O
door	O
is	O
fully	O
open	O
,	O
the	O
model	O
turns	O
on	O
the	O
door	O
open	O
limit	O
switch	O
,	O
and	O
the	O
PLC	B-Architecture
responds	O
by	O
turning	O
off	O
the	O
motor	O
which	O
raised	O
the	O
door	O
.	O
</s>
<s>
The	O
model	O
sees	O
the	O
Control	O
System/PLC	O
turn	O
off	O
the	O
motor	O
and	O
drops	O
out	O
the	O
motor	O
's	O
auxiliary	O
contact	O
.	O
</s>
<s>
For	O
instance	O
,	O
what	O
happens	O
if	O
the	O
Control	O
System/PLC	O
loses	O
the	O
motor	O
's	O
auxiliary	O
contact	O
as	O
the	O
door	O
is	O
rising	O
?,	O
Does	O
the	O
Control	O
System/PLC	O
turn	O
off	O
the	O
output	O
which	O
raises	O
the	O
door	O
?	O
</s>
<s>
The	O
control	O
strategy	O
is	O
incorporated	O
into	O
the	O
PLC	B-Architecture
logic	O
,	O
instead	O
of	O
being	O
contained	O
within	O
the	O
model	O
.	O
</s>
<s>
The	O
system	O
control	O
strategy	O
now	O
exists	O
in	O
two	O
places	O
,	O
in	O
the	O
model	O
and	O
in	O
the	O
PLC	B-Architecture
.	O
</s>
<s>
The	O
simulation	O
runs	O
with	O
the	O
internal	O
system	O
control	O
strategy	O
and	O
disables	O
the	O
external	O
connection	O
to	O
the	O
PLC	B-Architecture
.	O
</s>
<s>
Running	O
in	O
emulation	O
mode	O
disables	O
the	O
internal	O
control	O
strategy	O
,	O
and	O
enables	O
the	O
interface	O
to	O
the	O
PLC	B-Architecture
which	O
supplies	O
the	O
external	O
control	O
strategy	O
.	O
</s>
<s>
The	O
control	O
strategy	O
is	O
executed	O
in	O
the	O
PLC	B-Architecture
and	O
simultaneously	O
controls	O
the	O
real	O
system	O
and	O
the	O
model	O
.	O
</s>
