Question
Why is a capacitor of at least 10 micron (micrometer) F required to extend the EE-SP Photomicro Sensors cable?
Answer
EE-SP Series uses an LED for pulse illumination (modulated light). A circuit to fully stabilize the power supply voltage is not built into the Sensors, and so the voltage supplied to the Sensors will fall when the LED is lit due to the cable resistance and LED current if the cable is extended. A capacitor must be inserted (as a smoothing circuit) to prevent unstable operation due to the drop in voltage.
Standard Sensors for Detecting Ferrous Metals under Standard Conditions