SIEMENS LEVEL 1: FUNDAMENTALS OF SIEMENS AUTOMATION COMPLETE EXAM
QUESTIONS AND VERIFIED ANSWERS (2026/2027)
# QUESTION CORRECT RATIONALE /
ANSWER EXPLANATION
1 What does PLC stand Programmable Logic A PLC is a digital computer
for in Siemens Controller used for automation of
automation? industrial processes. Siemens
PLCs (like the S7 series) are
designed to control
machinery on factory
assembly lines, amusement
rides, or light fixtures.
2 Which Siemens STEP 7 (Classic) and STEP 7 is the legacy
software platform is TIA Portal (modern) programming environment
used for programming for S7-300/400, while TIA
S7 PLCs? Portal (Totally Integrated
Automation Portal) is the
unified modern platform for
S7-1200/1500 and beyond.
3 What does TIA Portal Totally Integrated TIA Portal is Siemens'
stand for? Automation Portal integrated engineering
framework that combines
multiple software tools
(STEP 7, WinCC,
SINAMICS, etc.) into a
,# QUESTION CORRECT RATIONALE /
ANSWER EXPLANATION
single unified platform for
automation projects.
4 What is the basic It is a compact, The S7-1200 was introduced
function of a Siemens modular PLC for to fill the gap between
SIMATIC S7-1200 small to medium simple micro-PLCs and
PLC? automation tasks. more powerful S7-300/400
systems. It supports
PROFINET, analog I/O, and
motion control.
5 What communication PROFINET PROFINET (Process Field
protocol is natively Net) is the open industrial
supported by Siemens Ethernet standard developed
S7-1200 and S7-1500? by Siemens. It replaced
PROFIBUS as the primary
communication protocol for
newer Siemens controllers.
6 What is PROFIBUS? Process Field Bus – a PROFIBUS (DP and PA
standard fieldbus variants) is a serial fieldbus
communication protocol widely used in
protocol used in Siemens automation for
automation. connecting field devices like
sensors, actuators, and
drives. It operates at speeds
up to 12 Mbps.
7 What is the function It executes the user The CPU is the brain of the
of the CPU in a program, manages PLC. It scans inputs,
Siemens PLC? executes the control logic,
,# QUESTION CORRECT RATIONALE /
ANSWER EXPLANATION
I/O, and handles updates outputs, and
communication. communicates with other
devices. Different CPU
models vary in memory,
speed, and features.
8 What is the scan cycle The repetitive process The PLC scan cycle consists
in a PLC? of reading inputs, of: (1) Read input image, (2)
executing the Execute user program, (3)
program, and updating Update output image, (4)
outputs. Handle communication and
diagnostics. This cycle
repeats continuously.
9 What is meant by A snapshot of the At the start of each scan
'process image' in physical input and cycle, the CPU copies input
Siemens PLCs? output states stored in states into the Process Image
CPU memory. Input (PII) and after
execution copies results to
the Process Image Output
(PIO), ensuring consistent
data during program
execution.
10 In TIA Portal, what LAD (Ladder TIA Portal supports IEC
are the three main Diagram), FBD 61131-3 languages: LAD
programming (Function Block (graphical rungs resembling
languages available Diagram), and STL relay logic), FBD (graphical
for basic ladder logic? (Statement List). blocks), STL (text-based
low-level), SCL (structured
, # QUESTION CORRECT RATIONALE /
ANSWER EXPLANATION
text), and GRAPH
(sequential function chart).
11 What does LAD stand Ladder Diagram LAD is a graphical
for in Siemens programming language
programming? modeled after relay ladder
logic diagrams. It is easy for
electricians to learn because
it mirrors the relay control
circuits they are familiar
with.
12 What is the difference NO contact closes In ladder logic: NO contact =
between a Normally (passes power) when energized when the
Open (NO) and the bit is TRUE (1); associated variable = 1. NC
Normally Closed (NC) NC contact opens contact = energized when the
contact in ladder (blocks power) when associated variable = 0. This
logic? the bit is TRUE (1). mirrors relay contact
behavior in electrical
schematics.
13 What is a coil in An output element that The coil (represented as '( )')
Siemens ladder sets a memory bit or writes the result of the rung
diagram activates an output logic to a bit address. When
programming? when power flows the rung is TRUE, the coil
through the rung. bit = 1; when FALSE, the
coil bit = 0. It is the output
side of a ladder rung.
14 What Siemens PLC SIMATIC S7-1500 The S7-1500 offers high-
family is best suited performance CPUs,
QUESTIONS AND VERIFIED ANSWERS (2026/2027)
# QUESTION CORRECT RATIONALE /
ANSWER EXPLANATION
1 What does PLC stand Programmable Logic A PLC is a digital computer
for in Siemens Controller used for automation of
automation? industrial processes. Siemens
PLCs (like the S7 series) are
designed to control
machinery on factory
assembly lines, amusement
rides, or light fixtures.
2 Which Siemens STEP 7 (Classic) and STEP 7 is the legacy
software platform is TIA Portal (modern) programming environment
used for programming for S7-300/400, while TIA
S7 PLCs? Portal (Totally Integrated
Automation Portal) is the
unified modern platform for
S7-1200/1500 and beyond.
3 What does TIA Portal Totally Integrated TIA Portal is Siemens'
stand for? Automation Portal integrated engineering
framework that combines
multiple software tools
(STEP 7, WinCC,
SINAMICS, etc.) into a
,# QUESTION CORRECT RATIONALE /
ANSWER EXPLANATION
single unified platform for
automation projects.
4 What is the basic It is a compact, The S7-1200 was introduced
function of a Siemens modular PLC for to fill the gap between
SIMATIC S7-1200 small to medium simple micro-PLCs and
PLC? automation tasks. more powerful S7-300/400
systems. It supports
PROFINET, analog I/O, and
motion control.
5 What communication PROFINET PROFINET (Process Field
protocol is natively Net) is the open industrial
supported by Siemens Ethernet standard developed
S7-1200 and S7-1500? by Siemens. It replaced
PROFIBUS as the primary
communication protocol for
newer Siemens controllers.
6 What is PROFIBUS? Process Field Bus – a PROFIBUS (DP and PA
standard fieldbus variants) is a serial fieldbus
communication protocol widely used in
protocol used in Siemens automation for
automation. connecting field devices like
sensors, actuators, and
drives. It operates at speeds
up to 12 Mbps.
7 What is the function It executes the user The CPU is the brain of the
of the CPU in a program, manages PLC. It scans inputs,
Siemens PLC? executes the control logic,
,# QUESTION CORRECT RATIONALE /
ANSWER EXPLANATION
I/O, and handles updates outputs, and
communication. communicates with other
devices. Different CPU
models vary in memory,
speed, and features.
8 What is the scan cycle The repetitive process The PLC scan cycle consists
in a PLC? of reading inputs, of: (1) Read input image, (2)
executing the Execute user program, (3)
program, and updating Update output image, (4)
outputs. Handle communication and
diagnostics. This cycle
repeats continuously.
9 What is meant by A snapshot of the At the start of each scan
'process image' in physical input and cycle, the CPU copies input
Siemens PLCs? output states stored in states into the Process Image
CPU memory. Input (PII) and after
execution copies results to
the Process Image Output
(PIO), ensuring consistent
data during program
execution.
10 In TIA Portal, what LAD (Ladder TIA Portal supports IEC
are the three main Diagram), FBD 61131-3 languages: LAD
programming (Function Block (graphical rungs resembling
languages available Diagram), and STL relay logic), FBD (graphical
for basic ladder logic? (Statement List). blocks), STL (text-based
low-level), SCL (structured
, # QUESTION CORRECT RATIONALE /
ANSWER EXPLANATION
text), and GRAPH
(sequential function chart).
11 What does LAD stand Ladder Diagram LAD is a graphical
for in Siemens programming language
programming? modeled after relay ladder
logic diagrams. It is easy for
electricians to learn because
it mirrors the relay control
circuits they are familiar
with.
12 What is the difference NO contact closes In ladder logic: NO contact =
between a Normally (passes power) when energized when the
Open (NO) and the bit is TRUE (1); associated variable = 1. NC
Normally Closed (NC) NC contact opens contact = energized when the
contact in ladder (blocks power) when associated variable = 0. This
logic? the bit is TRUE (1). mirrors relay contact
behavior in electrical
schematics.
13 What is a coil in An output element that The coil (represented as '( )')
Siemens ladder sets a memory bit or writes the result of the rung
diagram activates an output logic to a bit address. When
programming? when power flows the rung is TRUE, the coil
through the rung. bit = 1; when FALSE, the
coil bit = 0. It is the output
side of a ladder rung.
14 What Siemens PLC SIMATIC S7-1500 The S7-1500 offers high-
family is best suited performance CPUs,
