Photoresistor (LDR) symbol
Also called LDR, Light dependent resistor, Photocell
A resistor whose resistance falls as light falls on it. The two arrows pointing in mean light received.
ANSI / IEEE
IEC 60617What the photoresistor (LDR) symbol means
A resistor whose resistance falls as light falls on it. The two arrows pointing in mean light received.
ANSI and IEC symbols
Where you see it
Light sensing, dusk-to-dawn switches and photocells on outdoor lighting.
Related symbols
Frequently asked questions
What does the photoresistor (LDR) symbol look like?
On ANSI drawings: A zigzag with two arrows pointing in. In IEC 60617: A rectangle with two arrows pointing in.
Is the photoresistor (LDR) symbol the same in IEC and ANSI?
No. A rectangle with two arrows pointing in.
Where is a photoresistor (LDR) used?
Light sensing, dusk-to-dawn switches and photocells on outdoor lighting.
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