Figure 4. Resistance Budget Span Powering Two Repeaters (Example) - ADTRAN 239 H4R Installation And Maintenance Manual

An example problem is illustrated in Figure 4. For
this example, begin with three known measurements:
700 ohms first segment resistance, 800 ohms second
segment resistance, and 900 ohms third segment
resistance. See Figure 4 and the following steps to
solve the example problem:
1. Find the 900 ohms third segment resistance line
on the graph. This line is depicted in bold in
Figure 4. This line is the upper span power limit.
2. Find the 700 ohms first segment resistance point
on the vertical axis.
3. Find the 800 ohms second segment resistance
point on the horizontal axis.
HDSL4 Single Pair Resistance for Span Powering Two Repeaters and an H4TU-R
1200
1100
1000
900
800
700
600
500
400
400

Figure 4. Resistance Budget Span Powering Two Repeaters (Example)

61221445L1-5A
Resistance Budget
WITHIN LIMITS
500 600
Second Segment Resistance (ohms)
Section 61221445L1-5, Issue 1
4. Find the instance on the graph where the points
from steps 2 and 3 meet.
5. Is this point below the bold line defined in
step 1? Yes. Therefore, a circuit with these
parameters is capable of span powering two
H4Rs and one H4TU-R.
OUTSIDE LIMITS
700 800 900 1000 1100
9