Installation and Commissioning
Manual SCA-340 / SCA-340-L
sysmik.de
17
Terminal
point
Name
Function
1.1
U
S
24 V DC segment supply (segment circuit); The supplied voltage
is lead to the automation terminals via the potential routing
contacts.
2.1
1.2, 2.2
U
BK
/ U
M
U
BK
: 24 V DC bus controller supply, logic supply (U
L
) and analog
supply (U
ANA
)
U
M
: 24 V DC main voltage (main circuit); The supplied voltage is
lead to the automation terminals via the potential routing
contacts
1.3, 2.3
GND
Reference ground for the internal bus and automation terminals
(logic and analog circuit) and for the main and segment supply
(main and segment circuit).
1.4, 2.4
FE
Functional ground; Connecting the functional ground to this
terminal point is mandatory (see above). The terminal point is
internally connected to the potential routing contacts and the FE
contact at the back side of the enclosure.
Table 3.2.2.1.1:
Terminal assignment of supply connector
3.2.2.2
Power Dissipation Calculations for a Scalibur Controller
The power dissipation of the bus controller equals the sum of the power
requirements of the bus controller itself and the power loss of the internal power
supply for the whole Inline station:
P
SCA
=
P
O
+
P
USB
+
P
PERI
P
SCA
power dissipation of the bus controller
P
O
power requirements for operating the bus controller without
terminals and any external load (4.1 W)
P
USB
power dissipation of the bus controller caused by the load on
USB1 and USB2 (max. 500 mA each)
P
USB
= 0.7 V × ( I
USB1
+ I
USB2
)
P
PERI
power dissipation of the bus controller caused by the Inline IO
terminals
P
PERI
= 1.0 V × I
L
I
L
current consumption of U
L
Note:
The factors 1.1 V und 0.7 V result from the electrical efficiency of the internal power
supply unit.
Sample calculation: Power dissipation of a Scalibur in case of the maximum
possible current drawn from U
L
and a USB memory stick with 0.1 A current
consumption.
P
SCA
= 4.1 W + 0.7 V × 0.1 A + 1.0 V × 2.0 A
P
SCA
= 4.1 W + 0.07 W + 2.0 W
P
SCA
= 6.17 W