ELTEX TAU-36.IP - Appendix F. Calculation of Phone Line Length

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280 Universal Network Terminal TAU-72.IP/TAU-36.IP
APPENDIX F. CALCULATION OF PHONE LINE LENGTH
Electrical resistance/cable type relationship for 1km of DC subscriber cable lines.
Cable grade for subscriber
lines of local exchange
network
Core diameter
Electrical
resistance of
1km circuit, Ω,
max.
Line length, km
Standard TA
TA RUS
Rfull.max=2600Ω
TPP, TPPep, TPPZ, TPPepZ,
TPPB,TPP epB, TPPZB, TPPBG,
TPPepBG, TPPBbShp,
TPPepBbShp, TPPZBbShp,
TPPZepBbShp, TPPt
0.32
458.0
3.056
2.183
0.40
296.0
4.729
3.378
0.50
192.0
7.291
5.208
0.64
116.0
12.068
8.621
0.70
96.0
14.583
10.417
TPV, TPZBG
0.32
458.0
3.056
2.183
0.40
296.0
4.729
3.378
0.50
192.0
7.291
5.208
0.64
116.0
12.068
8.621
0.70
96.0
14.583
10.417
TG, TB, TBG, TK
0.40
296.0
4.729
3.378
0.50
192.0
7.291
5.208
0.64
116.0
12.068
8.621
0.70
96.0
14.583
10.417
TStShp, TAShp
0.50
192.0
7.291
5.208
0.70
96.0
14.583
10.417
TSV
0.40
296.0
4.729
3.378
0.50
192.0
7.291
5.208
KSPZP
0.64
116.0
12.068
8.621
KSPP, KSPZP, KSPPB, KSPZPB,
KSPPt, KSPZPt, KSPZPK
0.90
56.8
24.647
17.606
Phone line length calculation for different types of cable
1
:
1. Cable resistance at 20°C:
)/(
20
kmOhmRLR
SpCabCab
=
where:
20Sp
R
[Ω/km] -specific DC cable resistance at 20°С (table value).
Cable length:
)(
20
km
R
R
L
Sp
Cab
Cab
=
2. Loop length is twice:
CabLoop
LL = 2
3. Loop resistance at 20°C
2020
2
SpCabSpLoopLoop
RLRLR ==
1
Values from http://izmer-ls.ru/shle.html