Specifications

10-7
Cisco ONS 15216 EDFA2/EDFA2-A Operations Guide, R2.4
July 2004
Chapter 10 Troubleshooting
10.1.3 Troubleshooting Equipment Alarms
10.1.3.2 LCRNT1 and LCRNT2 (Excessive Pump Current) Alarms
These alarms occur when the input power exceeds input range and the ONS 15216 EDFA2 is overdriving
the pump laser to try to get the target Gain value. The manufacturer defines this condition as the drive
current at greater than 95% of end of life value. The current must drop to 90% of the end-of-life value
for the alarm to clear. Possible causes for this alarm are:
• The input power is too high for the gain setting: Reduce the input power by using an external
attenuator or by changing the OVERALLGAIN value using the ED-DWDM command.
• One pump laser is degrading: The unit needs to be replaced. Contact the Cisco TAC.
10.1.3.3 LTMP1 and LTMP2 (Excessive Pump Temperature) Alarms
These alarms occur when the pump laser has reached a critical temperature threshold. That is, the chip
temperature is deviating more than 10 degrees C from the manufacturer-defined set point.
• Ambient temperature is too high so the laser can't cool down: This condition is usually associated
with a CTMP alarm. See the 10.1.3.1 CTMP (Case Temperature Out of Range) Alarm section
above.
• The ONS 15216 EDFA2 has been operating with excessive pump current for a long period of time,
causing the pump(s) to overheat: This condition is usually associated with a LCRNT1 or LCRNT2
alarm. See the 10.1.3.2 LCRNT1 and LCRNT2 (Excessive Pump Current) Alarms section above.
10.1.3.4 PWRBUSA and PWRBUSB (Power Bus) Alarms
These alarms occur when the Power Bus voltage is out of the threshold range as defined by
PWRBUSMIN and PWRBUSMAX. The power bus threshold has a 1.5V tolerance and a 1.0V hysteresis.
The 1.5V tolerance prevents early alarm conditions due to a potential ±1.5V inaccuracy in the ONS
15216 EDFA2 voltage measurement.
The problem may be an inappropriate setting of the Power Bus alarm or a power failure. First, check the
alarm thresholds using RTRV-TH-EQPT (Example 10-2). The default values are POWERBUSMIN=420
(-42 VDC) and POWERBUSMAX=570 (-57 VDC). The command RTRV-ALM-EQPT responds with
which POWERBUS is outside of the range. If Power Bus B is not being used, check that
PWRBUSMODE=SIMPLEX using RTRV-TH-EQPT. If needed, use the command ED-EQPT to set the
POWERBUSMODE to SIMPLEX (Example 10-3). If all the settings are correct, verify the DC voltage
of the power source.
Example 10-2 Checking Power Thresholds
Amp01:ONS15216 EDFA2> RTRV-TH-EQPT:Amp01:PWR-A:123:PWRBUSMIN;
þAmp01 2004-03-17 00:02:15
M þ123 COMPLD
þ"PWR-A:PWRBUSMIN,,,420"
þ"PWR-A:PWRBUSMAX,,,570"
;
Example 10-3 Changing Power Bus Mode to Simplex
Amp01:ONS15216 EDFA2> RTRV-ALM-EQPT:Amp01:PWR-B:124;
þAmp01 2004-03-17 00:03:48
M þ124 COMPLD
þ"PWR-B:MN,PWRBUSB,NSA,3-16,20-39-21,,:\"Power Bus B Alarm\""