Overview of E+H Instrument Troubleshooting

E+H instruments are widely used in industrial processes, and their troubleshooting requires a systematic approach. This article introduces fault diagnosis steps and basic maintenance principles to help technical personnel quickly locate problems.

Determine the Approximate Fault Location

Accurately determining the fault location is the first step in maintenance and can be carried out through the following four steps.

Understand the Fault

Before inspecting the fault, ask the operator to learn about the conditions before and after the instrument was damaged and the phenomena when the fault occurred. For example, whether the display suddenly disappeared or suddenly showed the maximum or minimum value, first determine the type of fault. For pH measurement faults, you can directly operate the instrument to check the fault type.

Observe the Faulty Instrument

Power off and restart the faulty instrument, input a signal and observe whether there is any response, providing a basis for further diagnosis. You can toggle the corresponding switch, observe the instrument's response, and analyze the possible fault location. Some faults do not appear on the display, and abnormalities can be checked by restarting at breakpoints and operating switches.

Analyze the Cause

Based on the observation results, compare with the instrument or control system schematic diagram and wiring diagram to find the fault. Some faults may be caused by wiring or system issues.

Summarize the Approximate Fault Location or Scope

Infer various possible causes based on the fault phenomena. For example, if a mass flowmeter measurement value is inaccurate but there are no other errors, it needs to be checked item by item.

Basic Principles of Instrument Maintenance

Following the principles below can improve maintenance efficiency and reduce misjudgment.

Check Logic First, Then the Instrument

First check the working logic to determine whether it is a process cause or an instrument problem. First check whether the data recording system has any abnormalities. If the flow and level values fluctuate greatly and the transmitter has no problem, you can manually operate to see whether the values are normal. If not, it may be a process design issue.

Signal Output

First check whether the control system has a problem, then check the instrument wiring and signal output.

Easy First, Difficult Later

Check whether it is a single instrument fault or multiple instrument faults on site, then check the power supply settings. When a fault occurs, make a simple judgment first, which can save time for subsequent work.

To learn more, you can add the WeChat below for consultation, or join the instrument and meter exchange group for discussion, or call 153 2371 3323. More content is also available on the official account and official website http://ainstru.com/.