CALCULATING RING LENGTH
Page C-9
Use Figure C-2 to follow the calculations using the UTP Cable Length
Worksheet for Multiple Wiring Closets in the following example of a 4
Mbit/sec ring.
Example:
Multiple Wiring Closet
4 Mbit/sec
1. Actual Longest Lobe (given as 85 feet)
1. 85 ft.
2. UTP to Type 1 STP Conversion
2. X 2.54
3. Equivalent Type 1 Lobe Length
3. 216 ft.
4. Combined Trunk Length
93' + 69' + 24' = 186'
4
. + 186 ft.
5. Internal Drive Distance
5. 402 ft.
6. Maximum Drive Limit
6. 1263 ft.
6a. Internal Drive Distance
– 402 ft.
7. External Trunk Cable Budget
7. 861 ft.
8. Actual External Trunk Cable Length
95' + 70' + 175' = 340'
8. – 340 ft.
9. Result
9. 521 ft.
The result is positive and no repeaters or cable adjustments are
needed.