CALCULATING RING LENGTH
Page C-12
5. Internal Drive Distance
3. Equivalent Type 1 Lobe Length
6. Maximum Drive Limit
1. Actual Longest UTP Lobe
Multiple Wiring Closets
(1263 feet for 4 Mbit/s or 569 feet for 16 Mbit/s)
2. UTP to Type 1 STP Conversion
(2.54 for 4 Mbit/s or 2.91 for 16 Mbit/s)
(3) + (4) = (5)
4. Combined Trunk Length
(Sum of values for all closets, from Table below)
4 Mbit/sec
16 Mbit/sec
2.54
569 ft.
9. If you get a negative result, adjust
cable lengths or add active
components to the ring.
(1) x (2) = (3)
1263 ft.
2.91
7. External Trunk Cable Budget
8. Actual External Trunk Cable Length
X
2.
ft.
3.
4.
+
ft.
5.
ft.
6.
1.
ft.
7.
ft.
9.
–
ft.
8.
–
X
2.
ft.
3.
4.
+
ft.
5.
ft.
6.
1.
ft.
7.
ft.
9.
–
ft.
8.
–
6a. Internal Drive Distance
(from 5)
UTP CABLE LENGTH WORKSHEET
Internal Trunk Length for Multiple Wiring Closets
Number of
Number of Racks (Multiple Closets)
Concentrators
1
2
3
4
5
6
7
8
9
10
1
24
2
36
69
Values are Type 1
3
48
81
114
Equivalent in Feet
4
60
93
126
159
5
72
105
138
171
204
6
84
117
150
183
216
249
7
96
129
162
195
228
261
294
8
108
141
174
207
240
273
306
339
9
120
153
186
219
252
285
318
351 384
10
132
165
198
231
264
297
330
363 396
429
11
144
177
210
243
276
309
342
375 408
441
12
156
189
222
255
288
321
354
387 420
453
13
201
234
267
300
333
366
399 432
465
14
213
246
279
312
345
378
411 444
477
15
225
258
291
324
357
390
423 456
489
16
237
270
303
336
369
402
435 468
501
17
249
282
315
348
381
414
447 480
513
18
261
294
327
360
393
426
459 492
525
19
273
306
339
372
405
438
471 504
537
20
285
318
351
384
417
450
483 516
549