X20 system modules • Motor controllers • X20MM2436
1918
X20 system User's Manual 3.10
4.25.2.9 Protection
The power supply line should be protected by a circuit breaker or a fuse. In general, dimensioning the supply line
and overcurrent protection depends on the structure of the power supply (modules can be connected individually
or in groups).
Information:
The effective current for the power supply depends on the load but is always less than the motor
current. Make sure the maximum nominal current of 7 A is not exceeded on the power supply terminals
of the power element.
When choosing a suitable fuse, the user must also account for characteristics such as aging effects, temperature
derating, overcurrent capacity and the definition of the rated current, which can vary by manufacturer and type. In
addition, the fuse that is selected must also be able to handle application-specific characteristics (e.g. overcurrent
that occurs in acceleration cycles).
The cross section of the power mains and the rated current of the overcurrent protection used are chosen according
to the current load so that the maximum current load for the cable cross section selected (based on the type of
wiring, see table) is greater than or equal to the current load in the power mains. The rated current of the overcurrent
protection must be less than or equal to the maximum current load for the cable cross section selected (based
on the type of wiring, see table):
I
Mains
≤
I
b
≤
I
Z
Mains
≤
Fuse
≤
Line/cable
Maximum current load for cable cross section I
Z
/ rated current for overcurrent protection I
b
[A] depending on
the type of wiring at an ambient air temperature of 40°C in accordance with IEC 60204-1
Wire cross section [mm²]
B1
B2
C
E
1.5
13.5 / 13
13.1 / 10
15.2 / 13
16.1 / 16
2.5
18.3 / 16
16.5 / 16
21 / 20
22 / 20
Table 693: Cable cross section of the mains supply line depending on the type of wiring
The tripping current of the fuse must not exceed the rated current for overcurrent protection I
b
.
Type of wiring
Description
B1
Wires in conduit or cable duct
B2
Cables in conduit or cable duct
C
Cables or wires on walls
E
Cables or wires on open cable tray
Table 694: Type of wiring used for the mains supply line
4.25.2.10 Derating
To ensure proper operation, the following items must be taken into consideration:
•
The sum of the square of both effective currents (I
N
, peak value must not exceed 3 A) must not exceed 9
A². The boost current of 3.5 A for 2 seconds is an exception.
•
Modules next to the motor module can have a maximum power consumption of 1.0 W.
•
The derating values listed below must be taken into consideration
Example calculations
In the following examples, the calculation of I
N
² is used to check if the current operating state is permitted.
Output current
PWM 1
PWM 2
I
N
²
Operating state permitted
3.0 A
0 A
I
N
2
= 3 A
⋅
3 A + 0 A
⋅
0A = 9 A
2
Yes
2.1 A
2.1 A
I
N
2
= 2.1 A
⋅
2.1 A + 2.1 A
⋅
2.1A = 8.82 A
2
Yes
2.8 A
2.0 A
I
N
2
= 2.8 A
⋅
2.8 A + 2 A
⋅
2 A = 11.84 A
2
for max. 2 s
1)
1)
The cooling time, which means operation <9 A², must be at least 5 times as long as the time of the overload.
Summary of Contents for X20 System
Page 2: ......
