Using a digital multimeter (DMM) to perform measurements is very common in today’s world. Technicians use multimeters for equipment servicing, engineers use multimeters to troubleshoot, students use multimeters for lab research, and so on. Since digital multimeters have many functions, you need to know how to properly use your multimeter. Most multimeter failures are caused by improper use.
In this blog, you will learn four tips to avoid damaging your digital multimeter:
- Read the warning labels and specifications
Before you begin taking measurements with your digital multimeter, you should read the warning labels and specifications. Do not exceed the values provided in the specifications guide or as indicated by the yellow warning labels on the instrument. Always refer to the specification guide for conditions required to meet the listed specification.
Figure 1. Example of the 34470A digital multimeter’s rear panel showing warnings on the maximum voltage input and maximum current input.
- Ensure proper grounding
Always use the three-prong AC power cord supplied with the instrument. Proper grounding of the instrument will prevent a build-up of electrostatic charge that may be harmful to the instrument and you. Do not damage the earth-grounding protection by using an extension cable, power cable, or autotransformer without a protective ground conductor. It is good to check the AC power quality and polarity; Typical required AC voltage is 100 V, 120 V, 220 V ± 10%, or 240 V +5%/–10%. Typical expected grounding wire resistance is < 1 Ω; The voltage between neutral and ground line is < 1 V. If needed, you can install uninterruptible power supply [UPS] to power your meter.
- Avoid overpowering the digital multimeter
You can avoid damaging your digital multimeter by anticipating the signal level you’ll measure and presetting the proper signal range on the DMM. Overpowering the digital multimeter can damage the components inside the meter. For example, Figure 2 shows that the maximum voltage input of a 34461A digital multimeter is 1000VDC and 700 VAC. Before turning on or off the connected equipment or the DUT, reduce the signal level to the minimum safety level. This will prevent unexpected voltage or current swell or sag from affecting the input or output of your instrument.
Figure 2. Keysight’s 34461A digital multimeter front panel.
- Check for proper temperature and humidity
You need to keep your multimeter in a clean and dry environment. Typical temperature for storage condition is between – 40 and 75 °C; Typical humidity is < 95% RH. The DMM’s optimal operating temperature should be from -5°C to 23° You also need to ensure proper ventilation among racks so the temperature does not go up if all instruments are in use at same time. You should also frequently inspect and clean the cooling vents and fans.
Take good care of your instrument!
Using your instrument properly helps you and your organization save on maintenance costs. Therefore, it is always good to know the basic tips mentioned above to prevent damage to your multimeter.
To learn more, download the Tips for Preventing Damage to Digital Multimeters application note.
Visit Keysight.com or more info about Keysight digital multimeters.