Dc Current; Longitudinal Balance - JDS Uniphase SmartClass User Manual

Chapter 16 Test Results
Copper results
– measure total electrical loop length (includes length of bridged taps).
– find wet sections, bridged taps or open faults.
Opens/Capacitance: < 3% difference between Tip (A) and Ring (B) values indicate an acceptably
balanced loop. Anything greater indicates an unbalanced line or open fault, which inhibit digital
signals.
Table 49
Table 49 Opens/Capacitance result specifications (no ambient)
Range (feet)
0 to 2,999
3000 to 66000

DC current

You measure DC current to verify if enough current is present to operate equipment including the
phone or caller ID boxes.
DC current on Tip (A) to Ring (B) should be  23 mA at the NID. Anything less will not allow for differ-
ences in temperature and phone equipment will not operate during extremes.
Table 50
Table 50 DC current result specifications
Range
0 to 110 ma

Longitudinal balance

You measure longitudinal balance to:
– measure the quality of the pair: a measurement of the degree to which the Tip (A) lead is elec-
trically the same as the Ring (B) lead.
The more each lead is electrically identical (capacitance, inductance, impedance), the better the
pair will resist induced noise.
The balance result should be >60 dB. Anything less indicates electrical differences between Tip (A)
and Ring (B) that can lead to noise and other signal problems.
Table 51
Table 51 Balance result specifications
Range
35 to 70 dB
136
describes the opens/capacitance result.
Resolution
Range (meters)
(feet)
1 foot 0 to 999
1 foot 1,000 to 20,000
describes the DC current result.
describes the DC current result.
SmartClass TPS User's Guide
22035456, Rev 001
Resolution Range
(meters) (capacitance)
0.1 meter 0 to 44.9 nF
0.1 meter 45 nF to 1.04 µF
Resolution Accuracy
1ma 2% ± 1ma
Resolution Accuracy
1 dB 2 dB
Accuracy (applies to
capacitance only)
3% ± 45 pF
3%
June 2014