1. No lights when plugging into the switch
a. Modules are not compatible with the switch: Result is that the switch does not allow the modules to work. The brands may be incompatible: For example Cisco modules do not work in a Juniper switch.
b. Modules is defective, the gold finger is scratched , causes the modules to not be able to supply the power normally,
c. TOSA is defective or damaged.
2. Modules can’t be identified or DDM info. is abnormal :
a. Modules not compatible with the switches: Result is that the DDM info. can’t be read
b. I2C communication is abnomal: The rate isn’t matched with the switches;
c. I2C pull-up resistor is missed: Result is that the data can’t be transmitted correctly;
d. I2C program has problems, can’t match the customers’ switches.
3. No Link with switches :
a. Modules can’t work with the switch: The switch is not enabling the modules to work.
b. Receiver optical power is too small or can’t be received: Modules display RX_LOS can’t communicate: Can be read via RX_PWR of DDM. Some switches can display the alarm/ malfunction … working condition.
c. Receiver overload because bit error is too large to communicate: Usually happens on the long distance modules, direct connecting the modules with the patch cords , because the receiver rate is too large, and will damage the modules.
d. Modules is damaged: Return back to the supplier to test.
4. Modules have light, but the optical power is much lower than the standard data:
a. Optical fiber isn’t matched very well: Re-plug the modules and test again;
b. Optical fiber transverse is damaged or dirty: Replace the optical fiber and test again;
c. Using the wrong optical fiber, such as SM modules used as MMF.
d. Modules wavelength is different from the optical power meter.