Resistance cannot be measured in the light bar of the integrated ceiling lamp.

If the on voltage is not reached, there is no current and resistance cannot be measured.

According to ohm's law, voltage ÷ current = resistance. Generally, the voltage of each LED is 3 volts, and three lamp beads are connected in series as a unit. If 9 volts is used, the remaining 3 volts will be shared by resistors, so resistors are needed. According to the conventional current of LED, calculate the resistance, set a resistance number, and finally calculate the resistance value.