Festo Кабели и принадлежности - Manual (Page 463)

C. Technical appendix
C−17
Festo P.BE−SPC200−EN en 0901d
Formula for maximum cable length:
L
v
NJ ǒ
V
Bmin
* V
OUT ńVALmin
Ǔ
@ A @ Ë
CU
Nj
{2 @ I
2
) I
1
}
Meaning
· V
OUT/VALmin w 22.8 V
· V
Bmin
= minimum operating voltage supply
(on the power unit)
· Current I
1
= current for electronics etc. (24 V)
· Current I
2
= current for outputs, field devices and
proportional directional control valves etc.
(24 L)
· A = cross−sectional area (uniform e.g. 1.5 mm 2 )
·
κ
= conductance value of the cables
(uniform e.g.
κ
CU
= 56
m
mm 2 @
)
ġ
Example:
SPC200−CPU4 with basic components and field devices for
2Ăaxes:
I1 = 1 A
I2 = 2.3 A
V
Bmin
= 24 V
V
OUT/VALmin
= 22.8 V
κ
CU
= 56
m
mm 2 @ ġ
Result:
L
≤ 18 m for A = 1.5 mm 2
L
≤ 9 m for A = 0.75 mm 2