Transceiver for a period of time after the crash

This phenomenon caused by the switch, the switch will CRC error detection andlength check on all the received data, check out the faulty packets will be discarded, the correct packet forwarding. But this process has some erroneouspackets in the CRC error detection and length check are not be detected, suchpackets are sent out in the forwarding process will never, never be discarded, they will accumulate in the dynamic cache (buffer), never sent, and to buffer piles up, willthe phenomenon of crashes caused by switch. Because the heavy transceiver orreset switches can make communication back to normal, so users are usuallyconsidered transceiver problem.

Transceiver lamp does not light

The fault may be as follows: (a) to check whether the circuit breaker fiber; (b) to check whether loss of optical fiber line is too large, exceed the range of receivingequipment; (c) check the optical interface is connected properly, TX and remotelocal RX connection, remote TX and local RX connection. (d) examination of optical fiber connector insertion device interface is intact, whether the jumper type matching with the device interface, whether the device type matching and optical fiber transmission equipment, whether match length and distance.

Transceiver network packet loss

(1) the electric port and the network device interface transceiver, duplex mode or both ends device interface mismatch. (2) the twisted pair has a problem with the head of the RJ-45, detection. (3) optical fiber connection problems, jumper isalignment device interface, pigtail and jumper and coupler type matching.

Fiber optic transceivers connect back ends cannot communicate?

1 optical fiber connected in reverse, TX and RX on the fiber; 2.RJ45 interfaceconnection with external equipment is not correct (note through and splicing),optical fiber interface (ceramic ferrule) does not match, this fault is mainly embodied with photoelectric mutual control function in the 100M transceiver, such as fiber ferrule connected to APC the PC transceiver can't be normal communications inserted core, but by non photoelectric mutual control transceiverno effect.

Transceivers connect test method

If it is found that the transceiver is connected with the problem, please testaccording to the following method, in order to find out the cause of the malfunction:

1 proximal ends of test: computer on PING, such as PING words that optical transceiver is no problem. Such as proximal test cannot communication can bejudged as optical fiber transceiver fault.

2 proximal ends of test: computer on PING, such as PING barrier must be checked for optical connection is normal and fiber optic transceiver for transmitting and receiving power is within the permitted range. If PING general proof light pathconnection. You can judge the fault problem in the switch.

3 remote test and fault point judgment: the end is connected with the switch, the two ends of the PING, if no fault can be judged as fault another switch.

Transceiver when the broken?

(1) for attenuation of light is too large, the available optical power meter optical power measurement receiver, if in the vicinity of the receiving sensitivity range, the range of 1-2dB can be judged as the basic optical path fault.

(2) may be switch fault connected with transceiver, the switch into PC, namely two transceivers connect directly with PC, the two ends of the PING, such as no instablephenomenon can be judged as the basic switch fault.

(3) for the transceiver fault, the transceiver ends (not by PC switch), are no problem for PING, transfer a large file from one end to the other end (100M) above,to observe its speed, if the speed is very slow (200M file transfer more than 15 minutes), can be the basic judgment for transceiver fault.

1. The deduction

When we face the failure phenomenon and analyze the problem, we have unintentionally learned to use the elimination method to determine the direction of the failure.This method is to list all possible faults as comprehensively as possible according to the observed fault phenomena, and then analyze and eliminate them one by one.When eliminating, should follow the principle from simple to complex, improve efficiency.This method can be used to cope with a variety of failures, but maintenance personnel need to have a strong logical thinking, a comprehensive and in-depth understanding of switch knowledge.

2. Correlation method

The so-called comparison method is to use the existing Ethernet switches of the same model that can operate normally as the reference object and compare them with the fault switches, so as to find out the fault points.This method is simple and effective, especially in the case of system configuration failures. A simple comparison can be made to identify configuration differences, but sometimes it is not easy to find a switch with the same model and configuration.

3. The substitution method

Replacement is the method of finding fault points by replacing potentially faulty components with normal Ethernet switch components.It is mainly used for the diagnosis of hardware faults, but it should be noted that the replacement parts must be the same brand, the same model of the same kind of switch.

Of course, in order to make the troubleshooting work has rules to follow, can be in the fault analysis, should be analyzed according to the following principles.

(1) from the outside to the inside, if there is a fault in the switch, we can first identify from the various indicators on the outside, and then according to the fault indication, to check whether there is a problem in the 

corresponding parts inside.No matter whether the fault can be detected from the outside, the switch must be logged in to determine the specific fault and take corresponding measures to remove the obstacle.

(2) from soft to hard fault, who do not want to easily on the screwdriver to remove the switch again, so in the inspection, always from the system configuration or system software on the investigation.If the software doesn't solve the problem, the hardware does.For example, if a port is not available, we can first check whether the port the user is connected to is not in the corresponding VLAN, or whether the port is closed by another administrator, or other reasons on the configuration.If you rule out the system and configuration possibilities, you suspect that the real problem is a hardware failure.

(3). First easy then difficult in the case of more complex fault analysis, must first from simple operation or configuration to eliminate.This can speed up the speed of troubleshooting, improve efficiency.

1. Compared with civil Ethernet switches, industrial Ethernet switches can meet the needs of industrial field in terms of design, selection of components, strength and applicability.

2. Industrial Ethernet switches including mechanical environment adaptability, such as resistance to vibration and impact resistance, climate adaptability (work for - 20 ~ + 85 ℃ temperature requirement, at least for 10 ~ + 70 ℃, and corrosion resistance, dustproof, waterproof), electromagnetic environment adaptability, or electromagnetic compatibility EMC shall conform to EN 50081-2, EN 50082-2, EN 50082-3, EN 50082-4, the FCC standard, GB/T17626, IEC61000 etc.

3. Industrial Ethernet switch products should adapt to the harsh environment of industrial control site.The network equipment used in the industrial field must pass the surge test according to iec61000-4-5, GB/T17626.5 and other standards; the power frequency magnetic field immunity test according to iec61000-4-8, GB/T17626.8 and other standards; the pulse magnetic field immunity test according to iec61000-4-9, GB/T17626.9 and other standards; the voltage variation immunity test according to the standards iec61000-4-11 and GB/T17626.11.

4. Most industrial Ethernet switches are designed with wide voltage, operating voltage ranging from 18VDC to 36vdc, 220VA, 220VDC, 110VDC, etc.

5. The power supply of industrial Ethernet switches is generally designed as redundant double power supply, while that of civil Ethernet switches is single power supply.

6. Installation of industrial Ethernet switches: DIN rail, rack, etc.Installation mode of civil Ethernet switch: desktop and rack.

7. Industrial Ethernet switches working temperature wide working temperature (working temperature requirements - 20 ~ + 85 ℃, at least for 10 ~ + 70 ℃), narrow civil Ethernet switch operating temperature range.

8. Industrial Ethernet switch heat dissipation without fan housing, civil Ethernet switch fan heat dissipation.

Electromagnetic compatibility en50081-2 (EMC, industrial) en50081-2 (EMC, office) en50082-2 (EMC, industrial) en50082-2 (EMC, office).Industrial Ethernet switches to en 50082-2 (EMC, industrial).

10. Industrial Ethernet switch shell material alloy shell, high strength plastic shell, low strength.

11. Industrial Ethernet switch is fully enclosed and dustproof with good dustproof performance.

12. Industrial Ethernet switch link fault recovery time < 300ms.Civil Ethernet switch over 30 seconds.

      From the above indicators, it can be seen that civil switches are not up to the requirements of industrial environment. Therefore, in an increasing number of industrial automation fields, many users choose to use industrial Ethernet switches in order to ensure industrial security.

      The so-called industrial Ethernet generally means that it is technically compatible with commercial Ethernet (i.e. IEEE802.3 standard), but in product design, it can meet the needs of industrial site in terms of material selection, product strength, applicability, real-time, interoperability, reliability, anti-interference and essential safety.

      With the development and popularization of Internet technology, Ethernet technology has also developed rapidly. The improvement of Ethernet transmission rate and the development of Ethernet switching technology bring hope to solve the non-deterministic problem of Ethernet communication and make it possible to fully apply Ethernet in the field of industrial control.