Telecom Knowledge-How to prevent and avoid damage to the network analyzer?
2021-12-02
1. Ensure good grounding measures
■ Please be sure to use the supplied three-wire power cord with ground wire.
■ Good grounding measures can avoid the accumulation of static electricity, thereby avoiding the damage of the instrument by static discharge, and also avoiding the danger to the operator to the greatest extent.
■ When using other power supply cables or universal wiring boards, and when using autotransformers to change the power supply voltage, pay special attention to ensuring the integrity of the grounding system.
■ At the same time, pay attention to check the quality and polarity of the input AC power supply. Generally, the voltage used by the instrument is 100V, 120V, 220V, with an error of +/-10%, or 240V, with an error of +5%~-10%. The grounding resistance of the power ground wire is required to be less than 1 ohm, and the voltage between the neutral wire and the ground wire is less than 1 volt. Of course, you can configure UPS uninterruptible power supply if needed.
2. Pay attention to the yellow warning label of the meter and the test range of the meter
■ The signal input to the instrument cannot exceed the range indicated by the yellow warning label.
■ Please refer to the instrument technical indicator manual, which provides detailed indicators. This manual also contains the warm-up time required when the instrument is stable in measurement and the conditions and equipment required for measurement/adjustment of the instrument.
For example: model damage level
E5070B/E5071B +20 dBm, +/-10VDC
E5071C +26 dBm, +/-35VDC
E5061A/E5062A +20 dBm, +/-30VDC
3. Take care to avoid inputting signals beyond the allowable range
■ Before testing, understand the power range of the device under test in advance. Excessive power will cause damage to the RF port of the network instrument. Usually the maximum value of the RF input signal is "0.1~1 Watt or "0.2~2DCV.
■ Please adjust the output signal of the device under test to a small safety range before turning on the signal source path switch of the device under test. This can avoid damage to the network instrument due to the impact when the device under test is opened.
■ If necessary, DC blocking capacitors, limiters, or external attenuators can be used appropriately.
For example: Agilent 11867A RF limiter can provide protection for the instrument input circuit, it can reflect signals up to 10W average power or 100W peak power, so as to protect the attenuator, mixer, etc. in the working frequency band. Agilent 11742A can isolate below 45 MHz Up to DC signals, it can pass signals up to 26.5 GHz at the same time. For high-frequency oscilloscopes and microwave circuits that need to be biased, it can isolate low-frequency signals to protect valuable instrumentation equipment.
4. Protect the RF input and output ports
■ Be careful not to bend or bump the cable connected to the RF port of the instrument or the device under test.
■ Make sure that the cable connected to the RF port of the instrument or the device under test is properly supported and not suspended from the port.
■ Always use a torque wrench when connecting to the RF port.
■ Be careful not to confuse 50-ohm and 75-ohm cables or connectors.
5. Properly maintain RF cables and converters
■ Avoid repeatedly bending the cable; one excessive bending may cause permanent damage to the cable.
■ Minimize the number of connections to reduce wear and extend its service life.
■ Before using the adapter, check it to see if there are any dirt, dents or other signs of damage. A bad connector is likely to damage the good connector connected to it.
■ Clean dirty connectors to avoid poor electrical contact.
6. Pay attention to electrostatic protection
■ Static electricity can damage electronic components. If possible, work in an anti-static work area. Keep static-generating materials at least one meter away from the components.
■ Before connecting the cable to the analyzer, short-circuit the inner and outer conductors.
■ Before transporting or moving the instrument, please install electrostatic protection caps on all RF connectors.
7. Pay attention to check the temperature and humidity of the working environment of the instrument
■ Regularly check and clean the cooling vent of the instrument. Insufficient ventilation can cause overheating and damage to the instrument. The best working temperature is 23+/-5°C, and the guaranteed ambient temperature is
■ When installing the instrument in a cabinet, ensure normal convection inside and outside the instrument. The ambient temperature must be lower than the maximum operating temperature of the product, which is 4°C per 100 watts consumed. If the chassis consumes more than 800 watts, forced convection cooling must be used.
8. Properly transport the instrument and use proper packaging when transporting.
■ Please be sure to use the supplied three-wire power cord with ground wire.
■ Good grounding measures can avoid the accumulation of static electricity, thereby avoiding the damage of the instrument by static discharge, and also avoiding the danger to the operator to the greatest extent.
■ When using other power supply cables or universal wiring boards, and when using autotransformers to change the power supply voltage, pay special attention to ensuring the integrity of the grounding system.
■ At the same time, pay attention to check the quality and polarity of the input AC power supply. Generally, the voltage used by the instrument is 100V, 120V, 220V, with an error of +/-10%, or 240V, with an error of +5%~-10%. The grounding resistance of the power ground wire is required to be less than 1 ohm, and the voltage between the neutral wire and the ground wire is less than 1 volt. Of course, you can configure UPS uninterruptible power supply if needed.
2. Pay attention to the yellow warning label of the meter and the test range of the meter
■ The signal input to the instrument cannot exceed the range indicated by the yellow warning label.
■ Please refer to the instrument technical indicator manual, which provides detailed indicators. This manual also contains the warm-up time required when the instrument is stable in measurement and the conditions and equipment required for measurement/adjustment of the instrument.
For example: model damage level
E5070B/E5071B +20 dBm, +/-10VDC
E5071C +26 dBm, +/-35VDC
E5061A/E5062A +20 dBm, +/-30VDC
3. Take care to avoid inputting signals beyond the allowable range
■ Before testing, understand the power range of the device under test in advance. Excessive power will cause damage to the RF port of the network instrument. Usually the maximum value of the RF input signal is "0.1~1 Watt or "0.2~2DCV.
■ Please adjust the output signal of the device under test to a small safety range before turning on the signal source path switch of the device under test. This can avoid damage to the network instrument due to the impact when the device under test is opened.
■ If necessary, DC blocking capacitors, limiters, or external attenuators can be used appropriately.
For example: Agilent 11867A RF limiter can provide protection for the instrument input circuit, it can reflect signals up to 10W average power or 100W peak power, so as to protect the attenuator, mixer, etc. in the working frequency band. Agilent 11742A can isolate below 45 MHz Up to DC signals, it can pass signals up to 26.5 GHz at the same time. For high-frequency oscilloscopes and microwave circuits that need to be biased, it can isolate low-frequency signals to protect valuable instrumentation equipment.
4. Protect the RF input and output ports
■ Be careful not to bend or bump the cable connected to the RF port of the instrument or the device under test.
■ Make sure that the cable connected to the RF port of the instrument or the device under test is properly supported and not suspended from the port.
■ Always use a torque wrench when connecting to the RF port.
■ Be careful not to confuse 50-ohm and 75-ohm cables or connectors.
5. Properly maintain RF cables and converters
■ Avoid repeatedly bending the cable; one excessive bending may cause permanent damage to the cable.
■ Minimize the number of connections to reduce wear and extend its service life.
■ Before using the adapter, check it to see if there are any dirt, dents or other signs of damage. A bad connector is likely to damage the good connector connected to it.
■ Clean dirty connectors to avoid poor electrical contact.
6. Pay attention to electrostatic protection
■ Static electricity can damage electronic components. If possible, work in an anti-static work area. Keep static-generating materials at least one meter away from the components.
■ Before connecting the cable to the analyzer, short-circuit the inner and outer conductors.
■ Before transporting or moving the instrument, please install electrostatic protection caps on all RF connectors.
7. Pay attention to check the temperature and humidity of the working environment of the instrument
■ Regularly check and clean the cooling vent of the instrument. Insufficient ventilation can cause overheating and damage to the instrument. The best working temperature is 23+/-5°C, and the guaranteed ambient temperature is
■ When installing the instrument in a cabinet, ensure normal convection inside and outside the instrument. The ambient temperature must be lower than the maximum operating temperature of the product, which is 4°C per 100 watts consumed. If the chassis consumes more than 800 watts, forced convection cooling must be used.
8. Properly transport the instrument and use proper packaging when transporting.
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