Fault analysis and maintenance of monitor 1

Analysis and maintenance of fault of monitor

Medical monitor is a kind of system that can detect the important physiological and biochemical indexes of human body regularly or continuously, and has the function of storage, display, analysis and control. It sends out an alarm to the parameters beyond the specified range. Because it can monitor the important life parameters of patients in real time, continuous and long, it has become a large number of common equipment in hospital, and the rate of failure is relatively high. Because most of the monitor manufacturers do not provide circuit diagram, it brings some difficulty to maintenance. In particular, the import monitor circuit board is expensive, so the failure analysis to component level maintenance can save a lot of money for the hospital EEG machine.

To quickly detect and troubleshooting, we must first understand the main structure and principle of the monitor. Then, a unit or multivariate analysis method is used to find out which unit the fault occurs, and then further find out the fault components.

1. medical monitoring instruments are composed of six parts:

(1) power supply part

(2) signal detection part

(3) the analog processing part of the signal

(4) the digital processing part of the signal

(5) the recording section of the signal

(6) the alarm section.

2 examples of failure analysis and maintenance methods

2.1 PHILPS A3 monitor

Fault A:

There is a white stripe rolling up on the screen, all of which are normal.

Maintenance analysis:

According to the preliminary analysis of the fault phenomenon, it seems to interfere the fault, we first check the power circuit, the AC filter has no anomaly, and then the scanning circuit of the inspection field has no abnormal. The maintenance is in trouble. We carefully analyzed the fault phenomenon, found a type of fault free machine, replaced the suspected circuit board test machine, found that a small circuit board on the liquid crystal Pingbian has a problem. It is used by the main board output signal to display the LCD screen field by this plate. It determines the fault out of this version. We use the digital multimeter with waveform to make a contrast measurement, and find that there is an abnormal electrolytic capacitor and the replacement after the replacement.

Fault B:

The program control key on the panel is out of order and the screen is shown to be normal.

Maintenance analysis:

After checking the button of the key of the key, the elastic film is elastic and can not be popped down. We will open the spring piece by the back of the key and press it gently with the hand, so that the spring piece will be restored to the original elastic force, and the rear cover is fixed in the reverse order, and the rear cover is stuck with glue, and the opening test is restored to normal.

Fault C:

When the blood pressure is measured, the pressure time of the pump is too long, and the blood pressure is sometimes unable to measure.

Maintenance analysis:

The fault occurs mainly on the two components of the motor and the pump body. We should first judge whether power supply circuit failure or pump body fault, measuring power supply voltage normal, motor rotation is normal, analysis of the problem out on the pump body, the pump body dismantled, found diaphragm rupture, resulting in gas pump air leakage 1 normal work. We use the domestic air pump body installed on the original t machine, troubleshooting.