Alpha Technologies DSM3 for XM3 - Technical Manual - Manual (Page 84)

84 745-814-B11-001, Rev. C (03/2014)
9.3.1 Detailed LED Descriptions
REG - CM Registration
Once a downstream channel has been negotiated between the CM and CMTS, the modem
attempts to register with the DHCP server and obtain the Configuration File. This LED flashes
while the process takes place. Once the registration is complete, the LED will remain on solid.
This is the best indication that the DSM3 Series is communicating with the CMTS in the headend.
DS - Downstream Communication
This LED indicates the state of the CM's attempt to gain a downstream signal. This process may
take several seconds, depending on how long it takes the CM to locate a carrier signal and lock
onto a channel. The LED flashes while searching for the downstream DOCSIS channel and is on
solid when the downstream channel is locked.
ACT - CPE Activity
The CPE activity LED flashes to indicate that data is being transmitted or received between the
DSM3 Series and a network device.
LNK - Network Communication Status
The Ethernet link LED remains ON when there is an active connection on the Ethernet port (e.g.,
a computer is connected for local diagnostics).
Rx/Tx Power
The Rx/Tx PWR LED utilizes a tricolor LED to provide the installer a quick verification of the
modem transmit (Tx) and receive (Rx) RF power levels. The Rx/Tx PWR LED will illuminate
green when both the cable modem Tx and cable modem Rx RF power levels are within the range
as specified in the SCTE-HMS PropertyTable. The LED indicator illuminates blue when Rx and/
or Tx levels are within the warning range as specified by the SCTE-HMS PropertyTable. The
LED indicator illuminates red when Rx and/or Tx levels are outside the range as specified by the
SCTE-HMS PropertyTable.
Refer to the following table for default ranges in the SCTE-HMS PropertyTable:
9.0 Start Up and Verification
Parameter alarm Enable HiHi Hi Lo LoLo Deadband
Rx
docsIfDownChannelPower
(OID:1.3.6.1.2.1.10.127.1.1.1.1.6)
00
(0F*)
150 100 -100 -150 15
Tx
docsIfCmStatusTxPower
(OID:1.3.6.1.2.1.10.127.1.2.2.1.3)
00
(0C*)
550 500 00 00 15
* Values in ( ) denote behavior of the Rx/TX LED if alarmEnable bits are set to ‘00’.
By default, alarmEnable is set to 00 (disabled) to prevent unwanted SNMP traps but the LED
behavior will function as if the alarmEnable were set to the values in the above table. If the
alarmEnable bits are set to anything other than 00, the LEDs will then follow the behavior of
the desired enable bit setting.
The above default values translate into the following Rx/Tx Power LED color ranges:
LED Color Rx Range (dBmV) Tx Range (dBmV)
Green +10 to -10 0 to +50
Blue +15 to +10 and -10 to -15 +50 to +55
Red >+15 and <-15 >+55
In addition to the above SCTE-HMS PropertyTable entries, the Tx and Rx levels displayed on the
DSM3 Series Web page will each provide colored indicator bars that correlate to the RF LED and
SCTE-HMS PropertyTable thresholds.
Table 9-1,SCTE-HMS Property Table
Table 9-2, Rx/Tx Power LED Color Ranges