ABB LS25 laser analyzer troubleshooting

Saturation of direct/Saturation of harp. (Error): Direct signal or second harmonic saturation. When the concentration is too high or the optical path is too long, shorten the measurement optical path and reduce the receiving gain; Covering the receiving window and still reporting an error may indicate an electronic malfunction.

Communication and Explosion proof Version: Don't mistake 'unable to connect' for instrument failure

The front panel service port of LS25 is isolated RS-232, and the service software serial port defaults to 9600, 8 data bits, no verification, and 1 stop bit; The default IP for Ethernet is usually 192.168.1.237, with port 5001. You can change the IP, subnet mask, and gateway in the TCP/IP menu. Note that the LS25 Ethernet port will be turned off when using the service interface, and both should not be occupied simultaneously. When connecting to AO2000, the software versions 3.0.7/4.0.1 and ≥ 5.0.0 have different interfaces: for ≥ 5.0.0, it is recommended to connect X09 to the factory network and X08 to the analyzer; A single analyzer should be connected directly with a crossover cable, and multiple analyzers should be connected with switches. The IP address of the analyzer should be on the same network segment as X08 and unique; LS25 has been added to the "Setup system modules" of AO2000, with a 14 digit serial number and the first three digits must be 008, which is different for each unit. If AO2000 cannot read LS25, first check the network cable, switch, IP network segment, and port, and then check the AO2000 module serial number and IP settings.

The explosion-proof version should be separately noted. Class I Division 2 version is CSA certified T4, and the power box cannot be installed in Div.2. It must be placed in a non hazardous area or replaced with a suitable Div.2 power supply; Cable joints (Myers Hubs) and sealants shall be constructed in accordance with the manufacturer's and NEC/local specifications, and unused joints must be sealed; The service PC must be placed in a secure area. ATEX Zone 2 version is Ex nA nC [op is Ga] IIC T5 Gc, -20 ° C ≤ Ta ≤+55 ° C; receiving and main power cable connectors M20 (outer diameter 7-12mm), network and service connectors M16 (outer diameter 3.5-8mm); Unused connectors are sealed according to local standards; Wipe with a damp cloth before maintenance to avoid static electricity. Regardless of the version, the transmission/reception cable must not be replaced or changed in length beyond 20m without authorization, otherwise it may affect calibration and accuracy; The maximum length of the receiving cable is 150m, the maximum length of the power cable is 100m, and the service PC cable can be extended from 3m to about 10m.

Maintenance and span/zero point inspection: Move troubleshooting to daily operations

LS25 has no moving parts and does not require consumables, resulting in low maintenance. Most applications have an acceptable maintenance interval of three months or more. Regularly check the optical transmission in daily life, clean the window, check blowing and alignment when the transmission drops; It is recommended to introduce a sufficiently high concentration gas every three months for at least 10 minutes to confirm the response when testing the "zero gas" application; Calibration should be verified every 3-12 months, depending on accuracy requirements. Save the settings and measurement data after each calibration check for easy traceability in the future.

Span inspection can be performed using either a flow pool or an internal sealed pool. When the circulation pool is used for non corrosive gases, the 100mm space inside the receiving unit is utilized, while for corrosive gases, an external circulation pool is used; The span mode first stores the normal measurement absorption signal and continuously deducts it during inspection, requiring stable process signals; The default concentration is calculated based on a 1m optical path length, for example, a 1% span gas will display 0.1%. The internal sealed pool is moved into the optical path by a servo motor, including zero and span checks. The default span is 75-80% of the full range, and the entire process takes about 15 seconds. Span/zero point inspection is not a "recalibration", but a verification; If the inspection deviation is large, then determine whether proportional calibration or global calibration is needed.