Description of the problem

Fiber optic transmission equipment to build a new OSN6800 equipment, one of the PIU power supply can not be normal power, the corresponding PIU reported POWER_ABNORMAL alarm, observe the indicators on the PIU veneer, found that the brightness of the indicator with the other normal PIU is slightly darker.

Processing

1. The voltage is lower than the standard voltage of -48V required by the equipment.

2、PIU single board failure.

3, column header cabinet induced voltage caused.

Root cause

Vacuum switch is not connected

Solution

1. Unplug the connecting wire from the PIU at the scene and measure the voltage, which is found to be -53V, consistent with the main power supply.

2、Site replacement of PIU single board still can not be solved.

3, let the scene to observe the power supply connection of the server room, found that more than one equipment cabinets are arranged side by side, a cabinet power connection alignment are consistent, suspected of induced currents, and then instructed a line of the sub-frame power supply will be closed, and directly measure the top of the OSN6800 cabinet PDU output, and found that the voltage of this circuit has become 6.6V, which can be determined that the original voltage measured directly in the PIU is a false induction voltage, this voltage can not be loaded, so this leads to the problem; at the same time, the scene again checked and found that the server room customer power supply air switch connection error. It can be determined that the original voltage measured directly on the PIU is a false induction voltage, and this voltage can not be loaded, so it leads to the problem; at the same time, on-site inspection again, it was found that there was an error in the connection of the customer's power supply air switch in the server room, which was not connected at all, and after reconnecting it at the scene and closing the switch, the function of one of the equipment was restored to normal.

Suggestions and Summary

The main cause of the problem is the site power connection errors, resulting in delays in positioning, this case is designed to illustrate how to determine and locate the problems caused by induced voltage, I hope to give you a reference.

The technical information related to this chapter and the troubleshooting process of SDH equipment is collected and organized by Shenzhen Optical Transmission Network Technology Co. Our company specializes in Huawei SDH optical transmission equipment,SDH transmission equipment sales.