Panasonic S-LINK V, User Manual

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23
Chapter 1
Power Supply Capacity of System
Calculation of Voltage Drop Value
The transmission cables of the
S-LINK V
system may cause voltage drop due to the conductor resistance of the
cables themselves. For this reason, calculate the voltage drop value b24V and 0V, and supply the rat-
ed voltage to all the
S-LINK V
I/O units. However, it is not necessary to consider the voltage drop between the D
and G, and that of the control cables and connector link cables.
Use of a longer cable will cause more voltage drop. If the voltage drops below the rated voltage, the
I/O units will not work. In this case, use the local power supply unit.
CAUTION
Elongation of the transmission distance will cause more voltage drop
at the line end (b24V and 0V).
Voltage drop (V) = Cable length (m) × 2 × conductor resistance (Ω/m) × current (A)
Relation between the ambient temperature and allowable passing current when exclusive S-LINK V
cable SL-RCM100□ / RCM200 or SL-CBM100 / CBM200 (conductor cross section = 0.5mm
2
for each
cable) is used.
0
4
5
6
7
8
5 10 15 20 25 30 35 40 45 50 55 60
Allowable passing current (A)
Ambient temperature (˚C)
Rated voltage (V)
The rated voltage depends on the unit. Check the rated voltage, and then select the right power sup-
ply unit and cables.
CAUTION
Supply the rated voltage to each unit.
● Since the rated voltage to be supplied to the controller is +24V (-5%), the voltage supplied to the con-
troller should not be dropped below the following value:
24 - (24 × 0.05) = 22.8V
● Since the rated voltage to be supplied to the I/O units and end unit is +24V (-10%), the voltage sup-
plied to these units should not be dropped below the following value:
24 - (24 × 0.1) = 21.6V