VEGA VEGALOG 571 - Manual (Page 37)

VEGALOG 571 37
Data of the ib-IIC-circuit:
L
ext
max. = 1 mH
C
ext
max. = 580 nF
Data of the components:
Component Ultrasonic 1 overvoltage Line
Data sensor arrester
L
int
65
µ
H 0,13 mH searched
C
int
~0 1 nF searched
Determination of the line data:
L
int
= 1 mH – 0,065 mH – 0,13 mH = 0,805 mH
C
int
= 580 nF – 0 nF – 1nF = 579 nF
Calculation of the line length:
0,805 mH
l = ––––––––––– • m = 1,238 m
0,65
µ
H*
579 nF
l = –––––––––– • m = 4,825 m
120 pF*
Considering the max. VBUS-line length, the
line length in this example must not exceed
the value of 1000␣ m.
* typical values for unscreened two-wire lines: L‘ =
0,65
µ
H/m; C‘ = 120 pF/m
Electrical connection