Rockwell Automation DeviceNet Media Design Installation Guide User Manual
Page 103
Publication DNET-UM072C-EN-P - July 2004
Determine Power Requirements 4-25
D.[(1100 x (0.0045)) + (4 x (0.005))] x 0.25 = 1.24V
2. Add each device’s voltage together to find the total voltage for section 1.
0.11 + 0.45 + 0.79 + 1.24= 2.59V
3. Find the voltages for each device in section 2 using the equation for
thick cable.
SUM {[(L
n
x (0.0045)) + (N
t
x (0.005))] x I
n
} < 4.65V.
A.[(100 x (0.0045)) + (1 x (0.005))] x 1.5 = 0.68V
B.[(500 x (0.0045)) + (2 x (0.005))] x 0.5 = 1.13V
4. Add each device’s voltage together to find the total voltage for section 2.
0.68 + 1.13 = 1.81V
Since the total voltage does not exceed 4.65V in either section, the system will
operate properly - section 1 (2.59V < 4.65V) section 2 (1.81V < 4.65V).
The percent loading is found by dividing the total voltage by 4.65V.
Section 1%Loading = 2.59/4.65 = 56%
Section 2% Loading = 1.81/4.65 = 39%
D5
1.5A
D6
0.5A
Results