PRICING AND AVAILABILITY 800.827.0807
TECH SUPPORT 800.726.8663
RETURN FOR REPAIR 256.963.8722
www.adtran.com
61247002L1-22A
Warranty: ADTRAN will replace or repair this product within the warranty period if it does not meet its published specifications or fails while in service.
Warranty information can be found online at www.adtran.com/warranty.
TROUBLESHOOTING GUIDE
Condition Solution
At Power-Up, all Front Panel
Indicators are Off.
1. Verify that the channel bank or ONU BPS power LEDs are on.
2. Make sure that the unit is fully and correctly inserted into the channel bank
or ONU.
3. If step 1 fails, contact Alcatel customer service. If step 1 passes, but step 2
fails, replace the HTU-C NB/WB for Litespan.
The HTU-R has Power, but
LP1 or LP2 LEDs are Dark.
The Unit cannot Sync with the
HTU-C NB/WB for Litespan.
1. Simplex power for the powering for the HTU-R can be passed over cable
pairs that contain load coils or that are too long for HDSL synchronization.
Using a TIMS, verify that the circuit is within design limits.
2. The HTU-R powers-up as long as there is at least one good conductor on
each loop. To test, remove the protectors from the MDF and measure
t-r resistance to the HTU-R on both loops. The HTU-R places a 3 ohm
short between t-r on both loops. An extremely high impedance indicates an
open conductor. An extremely low reading on one loop may indicate a t-r
short in the field. In the field, measure t-t and r-r voltage with the HTU-C
NB/WB for Litespan installed. If these voltages are not present, open pairs
or mis-wiring is indicated. As with other circuits, standard resistance
measurements between each conductor and ground should also be used to
test for a grounded conductor.
3. A high-resistance open which degrades to the point that it causes the circuit
to lose sync can be “resealed” by reseating the HTU-C NB/WB for
Litespan. Test the cable pairs before reseating the HTU-C NB/WB for
Litespan.
The FAIL LED Remains On. 1. Verify that the channel bank or ONU BPS FAIL LEDs are off.
2. Verify that the equipment type for the HTU-C NB/WB for Litespan slot is
AHT1U. Using TL1, equipment type is shown with the command
rtrv-eqpt; AID, where AID is the access identifier (i.e., cot-1-15).
3. If step 1 fails, contact Alcatel customer service. If step 1 and step 2 pass,
replace the HTU-C NB/WB for Litespan. If step 1 passes but step 2 fails,
delete the equipment record (i.e., dlt-eqpt; cot-1-15 with TL1) and reinsert
the card, or equip the slot with the currently reserved equipment type.
The HTU-Rs DS1 LED is
Flashing, but No Errors are
Indicated by the HTU-C NB/
WB for Litespan.
A BPV, Frame Error (SF), or CRC Error (ESF) has been detected at the DS1
input. This indicates a wiring problem or a B8ZS/AMI mismatch between the
HTU-R and the CPE equipment. This is not an indication of problems on the
HDSL loops.
The FAIL LED is Off, but the
HDSL LED Remains Red.
1. Check that neither HDSL loop is open.
2. Check that neither or both HDSL loops are shorted.
3. Verify the loop conforms to CSA guidelines and is not too long. Loop loss
at 200 kHz should be less than 35.25 dB.
4. Verify that both HDSL loops have acceptable noise limits.
5. Verify that tip and ring of each HDSL loop belongs to the same twisted
pair.
6. If steps 1 through 5 pass, but the HDSL LED remains red, replace the
HTU-C.
7. If step 6 fails, replace the HTU-R and the HRE.
* This option is only applicable for software release 7.1.6 and lower.
TURN-UP GUIDE
1. Equip the COT slot for the ADS1U and the RT slot for the HTU-C NB/WB for Litespan.
2. Install the ADSIU in the COT, HTU-C NB/WB for Litespan in the RT, and the HTU-R at the
customer premises.
3. Make the cross connects between the ADSIU and the HTU-C NB/WB for Litespan.
4. Ensure that the (HTU-C NB/WB for Litespan) LEDs are as follows:
♦LOOP {Off
♦FAIL {Off
♦HDSL {Off
♦LP1 / LP2 zGreen
5. Provision the cards according to the circuit design and specifications.
6. Perform BERT testing.
NOTE: The HTU-C NB/WB for Litespan puts out –137 volts span power. It is capable of powering one
repeater and a remote unit.
The FAIL LED is Off, but the
HDSL LED Remains Yellow.
1. Check that the framing and line coding are set appropriately for T1 data at
the HTU-R and for cross-connect T1 data coming to the HTU-C NB/WB
for Litespan.
2. Check that the DS1 LED at the HTU-R is green.
3. If step 1 fails, change the appropriate framing and line coding. If step 1
passes, but step 2 fails, a problem may exist at the HTU-R T1 interface. If
the problem does not exist at the T1 interface, Replace the HTU-C NB/WB
for Litespan.
HDSL LED Yellow, HTU-R
DS1 LED Red (Customer Loss
of Signal).
To prevent major alarms from being reported in the central office, set the CLOS
option to LPBK or CDI.*
Running Excessive Errors on
the Loop.
1. Measure t-r resistance as described above. If the pairs are unbalanced by
more than 4 ohms, or a measurement varies a great deal, this could indicate
a high resistance open or an intermittent fault on the loop with the higher
measurement. A TDR is typically required to locate this splice for
correction.
2. Excessively long bridged taps can also cause errors. Check the records
and/or use a TDR to verify the location and length of bridged taps.
3. Using ADTRAN’s “Performance History” screen, it is often possible to see
that many more errors are being received on a particular loop or at a
particular unit. The fault is typically very close to the unit receiving the
most errors.
Condition Solution
HDSL
HTU-C using Narrowband / Wideband for Litespan®
