Electronics Equipment Module UCCS Physics Labs Table of Contents Resistor color code DMM Power supplies 2 3 4 FYI FYI Thomas Edison designed a helicopter that would work with gunpowder. It ended up blowing up and also blew up his factory. Electronics Equipment Module - 1 Resistor Color code Common resistors contain a code of colored bands that expresses the value of its resistance and the uncertainty of this value. Resistor 4th band 3rd band st 2nd band 1 band The forth band is either gold or silver. Therefore, to find the first band go to the opposite side of the code as the gold or silver band. Using the resistor code Bands 1 and 2 are the first two digits in the resistance value. The third is the power of 10 multiplier. The last band is the uncertainty of the resistance. The following colors correspond to these numbers or multiplier. Color Number Multiplier black 0 10 = 1 brown 1 101 = 10 red 2 102 = 100 orange 3 103 = 1000 yellow 4 104 = 10,000 green 5 105 = 100,000 blue 6 106 = 1,000,000 violet 7 107 = 10,000,000 gray 8 108 = 100,000,000 white 9 109 = 1,000,000,000 gold silver Uncertainty (%) 0 10-1 = 0.1 -2 10 = 0.01 Electronics Equipment Module - 2 5% 10 % Example What is the value with the following bands: brown - black - red - gold first digit = first band = brown = 1 second digit = second band = black = 0 multiplier = third band = red = 102 = 100 Therefore, 10 X 102 = 10 X 100 = 1000 With an uncertainty of 5 % (forth band gold). It’s just that easy!! DMM (Digital Multi-Meter) Measurement select AC/DC Voltage(V) Current(A) Resistance(k) Signal connection (Note: use the “mA” terminal and “Common” to measure a current, 2A MAX! Otherwise, use the “Common” and “V/kΩ/S” terminal for the rest of the measurements. On/Off button Measurement Range select The DMM (Digital Mutli Meter) is the great for measuring stable voltages, currents and resistances. Therefore, we shall be using this device whenever we need a DC circuit measurement or something that will not change with time. In order to measure something that changes with time we will use the computer, it is perfectly suited for that job. Electronics Equipment Module - 3 Power Supply Voltage Meter Current Meter Current Controls Voltage Controls Power Button Output Connectors There are separate controls for the voltage and current outputs. Be careful that the current does not get too high! Keep the current knob turned down as low as possible. Your instructor will help you with this until you get the hang of it. Electronics Equipment Module - 4