NETIK-CAD Electrical blocks for Autocad ®


Memento - 1    Generalities

Standard paper format
Color code designation
Protection grade IPxx
Circuit-breaker curve
Security category
Designation of electrical material

Standard paper format
Paper format Serie 'A'
Value in mm
841 x 1189
594 x 841
420 x 594
297 x 420
210 x 297
148 x 210







Color code designation
Black BK   Grey G7
Brown BN White WH
Red RD Rose PK
Orange OG Gold GD
Yellow YE Turquoise TQ
Green GN Silver SR
Blue BU Green-Yellow GNYE
Violet VT    








Protection grade IPxx1 X2 X3
Protection against dust   Protection against liquid   Protection level against mechanical shock
X1   X2   X3 Hammer weight [kg] Height of fall [m] Energy of the shock [J]
no protection
no protection
0,5 0.15 0.1 0.2
protection against solid body > 50mm
protection against dripping water
1 0.15 0.15 0.3
protection against finger contact and to solid body > 12mm
protection against dripping water (when tilted to 15° N)
1,5 0.15 0.2 0.4
protection against tools contact and to solid body > 2,5mm
protection against spraying water (when tilted to 60° N)
2 0.15 0.25 0.5
protection against thin tools contacts and to solid body > 1mm
protection against spraying water (in any direction 360°)
3 0.25 0.2 0.6
full protection against contact and the deposit of dust
protection against water jet
4 0.5 0.2 1
dust tight
protection againgst heavy seas
5 0.5 0.4 2
6 1.5 0.27 4
complete protection against submersion
7 1.5 0.4 6
8 5 0.2 10
9 5 0.4 20
10 15 0.235 35
11 15 0.4 60



Tripping curve of circuit-breakers
Tripping curve type
I short-circuit / I overload
3 ... 5
great length of cable
5 ... 10
standard use
10 ... 14
motors, transfos
12 without overload
for the motors, with overload relay combined to the contactor
10 ... 14
Z 2.4 ... 3.6
U 5.5 ... 8.8
tertiary sector, industry, farming
2.6 ... 3.85
great length of cable


Security category standard EN 954-1
Category Brief description of the rules Behavior of the system Principle
B (basic) The safety-related parts of machine control systems and/or their safety devices and components shall be designed, constructed, selected, assembled and combined in accordance with the relevant standards so that they can withstand the expected influences A fault can lead to a lack of security function Largely characterised by the selected devices
1 Same as B + use of principles and certified security devices Same behavior as B, but with a better reliability

Safety-related parts of control systems must be designed so that their safety function(s) are checked at suitable intervals by the machine control system. The safety function(s) must be checked:
(a) at the machine start-up and prior to the initiation of any hazardous situation, and (b) periodically during operation, if the risk assessment and the kind of operation show that it is necessary

This check may be initiated automatically or manually. Automatically, for example, the check may be initiated by a signal generated from a control system at suitable intervals. The automatic test should be provided by preference. The decision about the type of test depends on the risk assessment and the judgement of the end user or machine builder. 

The result of the test shall allow operation if no fault has been detected, or shall generate an output to initiate an appropriate control action if a fault has been detected. This requires a second, independent shutdown route

In some cases Category 2 is not applicable because the checking of the safety function cannot be applied to all components and devices. Moreover, the cost involved in implementing Category 2 correctly may be considerable, so that it may make better economic sense to implement a different category.
In general Category 2 can be realised with electronic techniques. The system behaviour allows that: the occurrence of a fault can lead to the loss of the safety function between checks; the loss of the safety function is detected by the check.

A fault is not recognised until the peridic safety check is not done Largely characterised by the structure of the control
3 Safety-related parts of control systems must be designed so that a single fault in any of these parts does not lead to the loss of the safety function. Whenever reasonably practicable, the single fault shall be detected at or before the next demand upon the safety function. This does not mean that all faults will be detected. The accumulation of undetected faults can lead to an unintended output signal and a hazardous situation at the machine. The safety function is maintained with the loss of a single fault
4 Safety-related parts of control systems must be designed so that a single fault in any of these parts does not lead to a loss of the safety function; the single fault must be detected at or before the next demand upon the safety functions (e.g. immediately at switch on, at the end of a machine operating cycle). If this detection is not possible, then an accumulation of faults shall not lead to a loss of the safety function. The safety function is maintained, even with the accumulation of faults
It is to the customer to specify the security category complying with EN 954-1 for specialised systems

Safety risk analysis must be complying with EN 1050 or EN 292-1. The contracting party configure the application on basis of these security rules.



Designation of electrical material
The designating code appear at a suitable place near the symbol. It establish a relation between the considered material in the equipment and the documents (schematics, bill of material, developped schematics, instructions). For the ease of the maintenance, it can be brought in full or partially on the material or in the proximity. The designation of electrical material is done by blocks identified by symbols, these last serving to differentiate the blocks 1,2,3,4.
Block 1 Upper function from where come all relation with other parts of the installation locally or in the behavior.
Block 2 implanting of the material
Block 3 identification of the material
Block 4 designation of terminal and wires



= 1 + 2 - 3A 3B 3C : 4

Upper function (equipment)

  location   type

sequence order

function   connexion
The following types are prefered
3A-3B-3C or
3A-3B or
Letters for the block 3A - From now on the text has to be translated (be patient)
The following table show the characteristic letters for the materials. Beside the letter determining the type of material, we can use the letters determinig its use so that the designation reinforce the identification of the device.

A Assembly, Sub-functionnal-assembly.

Combination of device making an unit; from construction but that it is not possible to classify with another letter
Tube amplifyer or with transistor, magnetic amplifyer, laser, maser.
Electric Variator.

Programmable Logic Controler (PLC).
B Converter of non electric value in electric and inversely Converter of pressure measure, quantity, temperature, speed, level. Proximity detector. Thermocouple, fotoelectric cel, electrical dynamometer, transducer with cristal, microfone, reading head, synchro-transmetteur.
C Condensator  

Binary element
Time delay device

Memory device
Devices and integrated circuits of binary equipment and digital command, regulation and calculus. Monostable bridge or bistable, magnetic memory, recorder on tape or on disk.
E Miscellaneous Devices not included here such as the lighting and heating devices
F Protection device Circuit-breaker, fuse, protection relay, manostat, overvoltage limitator, lightning protector
G Generator, supply device Generator, alternator, converter, supply box, charger, battery, oscillator,  oscillator with quartz
H Indicator device Optical and accoustical signaling device
J   Free
K Contactor, relay Power contactor, auxiliary contactor, timedelay relay, auxiliary relay
L Coil Transducer, induction coil, blocking coil
M Motor  
N Amplifyer, regulator Device for command equipment, for regulation and for analog calculus
P Measuring device, Control device Measuring device, indicator and recorder, counter, hour commutator
Q Cutting device for strong current Circuit-breaker, loadswitch, motor circuit-breaker
R Resistance Adjustable resistance, potentiometer, rheostat, shunt, thermistance
S Control commutato Command auxiliary, push-buton, selection switch, end limit-switch, telefone dial wheel, connexion stage
T Transformer Current transformer, voltage transformer
U Modulator, converter of electric value Codification device, inverter, frequence discriminater, frequence converter, converter rectifier, autonome inverter
V Semi-conductor, tube Transistor, thyristor, diode, electronic tube
W Conductive Bus bar, wire, cable, wave guide, coupleur, directif wave guide coupleur, dipole, parabolic antenna
X Terminal, plug and socket Plug and socket connexion, clips, test plug, terminal plate
Y Mechanical device electrical actuated Brake, clutch, valve engine, pneumatic electrovalve
Z Filter, corrective, limitator RC or LC filter, device limitating the interference, smooth-out device, differentiel transformator, cristal filter
Letters for the block 3C
A Auxiliary function, "OFF" function
B Direction of working
C Numerical counting
D Differenciation
E "ON" function
F Protection
G Controle
H Signaling
J Integration
K Use of push-button
L Wire location
M Main function
N Measure
P Proportional
Q Status (starting, stop, limitation)
R Reset, clearing
S Memorisation, storage
T Delaying, timing
U -
V Speed (acceleration, breaking)
W Summing
X Multiplication
Y Analog
Z Digital


Sample of identification
Full identification in which the essential subdivision indicate the location =R057+5A3-Q6:2
Terminal 2
of circuit-breaker 6
from sub-assembly A3
in assembly 5
in the room 057
Identification in which the essential subdivision indicate the function of the element in the full equipment =3T7-M84
Motor 84
Pomp 3 of cooling of turbine 7 in assembly
Identification for indication of type, of sequence number and of function -K3M
3=sequence number
M=main function
Sample of a plant            
Sample of a plant            
Sample of installation plan            
Sample of installation pla