Nt 
motors for low tension at full pressure must be at least as much as indicated in 
the following table: 
Axle capacity 
Kilo- 
watts 
Horse- 
Dower 
0.35 
L5 
35 | 
11 
30 
75 
0.5 
Number of revolutions per minute 
2.000 
1.500 
750 
275 
Power Power Power 
factor factor factor 
0.72 0.69 0.60 
.78 74 L687 
.81 .78 .73 
.85 .83 L7® 
.87 . 86 +2 
.R8 Re ww 
Power 
factor 
7g 
0 
The power factor for single phase motors may be 0.03 lower. The power 
factor for high-tension motors may be 0.03 lower. The required power factor 
for motors with axle capacity or a number of revolutions not mentioned in the 
table must be in ratio to the figures mentioned in the table. 
3. Before operating motors the electricity service must be offered an oppor- 
tunity to, examine the same at the expense of the party who has installed them 
or the party who uses the current. 
4. The mountings of motors and the metal parts of the starting resistances 
which are not under tension, as well as all the handles, must be properly con- 
nected with the earth by means of tin-covered copper wire or cable. 
The earth connection may not be joined to the neutral wire of the installation, 
nor to gas pipes. The connection with the earth must be approved by the 
electricity service. 
5. Every motor must be provided with working regulations and a switching 
scheme which shows in which way it is disconnected. . 
6. Motors with an axle capacity of not more than 1 kilowatt (1.36 lorsepower) 
may be switched on with an ordinary 3-pole switch. 
7. Motors with an axle capacity of more than 1 kilowatt up to not more than 
2 kilowatts for intermittent operation and of not more than 3 kilowatts for 
continuous operation which have a short-circuit or rotor, must be started with a 
starting resistance in the stator or a star-delta switch to be approved by the 
electricity service. Intermittent operation is considered to be operation of the 
motor for not more than 5 consecutive minutes. The star-delta switch must be 
of such a design that it can be switched in only two movements from the dis- 
connected position into the delta position; when switched off it must leave the 
motor entirely without tension. 
8. Motors with an axle capacity larger than 3 kilowatts must be provided 
either with a slip-ring armature and be started by means of a tarting resist- 
ance in the rotor circuit or with a short circuit or short-circuit rotor and be 
started with a starting transformer in the stator, or be equipped with another 
special device approved by the electricity service by which the strength of the 
starting current is kept within certain limits. When starting the rofor circuit 
may not have a tension higher than 300 volts. 
9. Motors with a capacity of over 8 kilowatts must be equipped with one or 
more devices which break up the current carried in all phases and make it impos- 
sible to start anew until the starting device is brought back to neutral, when 
the voltage of the system decreases fo more than 50 per cent of normal (auto- 
matic protection against low tension) for longer than 5 seconds or when the 
carrying of the current is interrupted in one of the phases. 
10. The starting strength of current which is taken from the system, except 
in special cases, may not be more than 10 amperes higher than the normal full 
tension strength of current of the motor, except in installations where several 
motors are being used; the starting strength of current in such installations 
may not be higher than that of the largest motor. 
11. Motors with an axle capacity of more than 10 kilowatts must have in one 
of the phase wires an ampere meter, which must be easy to read for the persons 
who operate the starting device. 
12. On the starting device the off position must be indicated, and the connect- 
ing installation must be clearly indicated by an arrow. An inscription must 
state that connecting must be done slowly. It must be impossible to leave the