So while the internal electronics are rated at more than 500mA, the fuse is added for protection, but above 200mA your measurements could be 20% off. Often, the higher you go (in terms of input voltage or current) the less accuracy you have (components warming up causes value drifting, eg a resistor value increases). If you were to make your own meter using normal standard components, you’d be lucky to be accurate with ☒0% (based on the values of resistors, capacitors, and any critical components). If you go above the specified number (ie 30 volts or 300mA) the accuracy can not be maintained. On most meters numbres such as 1 10 and 100 are used to indicate their range, however with theses meters being so cheap and disposable, they have an issue with accuracy. Notice how most of the numbers on the front are in units of 2, 20, 200 and such.
Sharp eyes and excellent question! I’ll be glad to answer. This guide walks through the fuse replacement process from start to finish, pointing out the various hazards along the way, ensuring a problem free fix.
#HOW TO USE A CEN TECH 7 FUNCTION DIGITAL MULTIMETER SKIN#
Skin oil on the glass can degrade the natural lifetime of the fuse and holding fuses by their center using fingers or pliers could crush the fuse body. Avoid grabbing the fuse by the middle glass or white ceramic center body. Fuses can be fragile and should be treated with care when handling them, just as with any electronic device. Giving the meter a new fuse can restore functionality. When the fuse is blown, the device can not pass or measure current, but the other 6 functions continue to work like normal. The current measuring modes, located on the right side of the dial, are the only modes that rely on the protection of the fuse. These 7 function digital multimeters have multiple modes of operation, with current measuring functionality that set them apart from the cheapest of meters. Fuses protect the device from damage and are cheaper to replace than the entire device. Next thing you know, there's a flash and a pop and your fuse is dead.
Even the most experienced electrical engineers forget to properly set their meters when making a quick voltage check.