Paperless recorder repair knowledge

In many industrial sites, paperless recorders need to monitor records, instrument input signals, such as the flow signal of the flowmeter, the pressure signal of the pressure transmitter, the temperature signal of the thermal resistance and the thermocouple, etc., through the high-performance 32-bit ARM micro The processor performs data processing. On the one hand, it is displayed on a large-screen liquid crystal display screen in various forms. On the other hand, the data of these monitoring signals are stored in the built-in large-capacity memory chip of the machine so as to be recorded in this record. On the instrument directly for data and graphics queries, paging and printing. The paperless recorder eliminates the stylus pen and recording paper used in traditional paper recorders, improves the quality of the recorder itself, enhances the stability and reliability of the recorder, and more importantly, reduces the operating cost of the recorder. . In the process of using, there will still be many problems. Whenever people use paperless recorders, it may be because the use of time is too long or our abnormal operation may cause equipment problems. Discuss with you the need to understand the basic principles of some paperless recorders when this happens. The following points need attention in maintenance and repair:

1. When disassembling and adjusting the instrument, record the original position for recovery.

2. When troubleshooting a paperless recorder in a wet environment, it is necessary to measure whether the various points on the printed circuit are unobstructed, because the main fault in this case is corrosion of the copper foil.

3, repair precision paperless recorder, such as accidentally fly the small parts, you can take the magnet scanning and line-of-sight scanning method to find.

4, with a multimeter ohm block, remember not to live measurement.

5. When detecting the filter capacitor in the power supply, the positive and negative electrodes of the electrolytic capacitor should be short-circuited first, and the short-circuit line should not be used to discharge the capacitor instead of the lead wire, because it is easy to blow the core wire. It is possible to take a 220V, 60 to 100W lamp with a cap lead, which is connected to both ends of the capacitor. The lamp will flash at the moment of discharge.

6. When the internal circuit of the paperless recorder is inspected, if the contacts and circuit boards of the mounting component are coated with insulating varnish, the common parameters of the parameters can be measured by using ordinary hand-stitch welding on the test leads of the multimeter so that the paint layer can be directly measured. Point, without peeling off the paint layer.

7. Do not hot plug various control boards and plugs. In the case of power-up, the plug-in control board will generate a strong induced electromotive force. At this moment, the instantaneous counter-attack voltage is very high, and it is easy to damage the corresponding control board and plug.

8, do not blindly knock overhaul during maintenance, so as not to expand the failure, the more repair and more bad.

9. When using logic pens and oscilloscopes to detect signals, be careful not to make the probes short-circuit by simultaneously touching two measurement pins.

Through an overview of paperless recorder maintenance knowledge, I believe that in the future when we encounter some of the above-mentioned problems, even if we are not professional repair personnel can also do a simple repair and treatment of the equipment.