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Reverse photo eye so it turns on at daytime

Day ON photoeye

Day ON photoeye

15 amps 120 volt
3 year warranty/ $49

Buy from my affiliate links:
Day on photoeye at Amazon
ST01 timer reverse photo eye

ST01 timer: reverse photo eye

240 Volt photo eye

Why is this a photoeye? Where is the photoeye???
ST01 timer is astronomic dusk to dawn timer. Same as photoeye is dusk to dawn.
When red and blue wires are connected, timer reverses into dawn-to-dusk
So load is ON in day and OFF at night
Adjustable to time zone,
ST01 timer works with any voltage/ 12-24-28-120-208-240-277 Volt
ST01 is battery operated and needs no voltage to run timer.
Freezing temps shorten battery life to 20 days.
ST01 has 1 year warranty, Ei600 has 5 year warranty
Intermatic ST01 timer at Amazon
Ei600 5-year warranty timer at Amazon
CR2 replacement battery at Amazon

Intermatic timers: ST01C & Ei600
More wiring for ST01C + ST01C programming

Sell sheet with model numbers
Load ratings for Intermatic timers/ pdf
Load rating for ST01 timer: 120V ac, 6A, 208-277V ac; DC Loads 4A 12V dc, 2A 28V dc; Motors 1HP 120VAC, 2HP
240V ac, Ballast 16A 120V ac, 208-277V ac; Resistive 20A 120-277Vac.
ST01 dusk-dawn timer

Other uses for ST01 timer:

Programmable or dawn-dusk or dusk-dawn, any voltage or no voltage
ST01 timer controls water heater or any 240 volt load
Reverse ST01 using Intermatic air switch   /
Intermatic air switches
Use ST01C for 4-way timer
ST01 24 volt DC photoeye
Convert single-pole switch into 3-way switch using ST01/
How to add a switch   How to add 3-way switch
24 volt programmable timer

Omron LY23 AC Model terminals/ back to front:
7-8 magnet terminals (turned opposite direction from other pins)
5-6 common terminals
3-4 NO normally open terminals (power is off when relay off)
1-2 NC normally closed terminals (power is On when relay is off)
Load rating 7.5 amps AC
900 watts incandescent @ 120V
1800 watts incandescent @ 240V
1/4 Hp motor @ 120V; 1/2 Hp @ 240V

Reverse photo-eye so Load turns ON in daylight

To reverse operation of photo-eye
So Load comes on during daylight hours
photo eye connected to DPDT relay

30 Amp relay x 80% = 24 amp max up to 2880 watt @ 120V or 5600 watt @ 240V
30 amp 10 gauge wire up to 2 Hp @ 50' or 1.5 Hp @ 100' @ 120V See load charts
Use Omron 120volt LY2-AC 8-pin relay for 7.5 amp.
    NO NC Relay
    7.5Amp Omron         30Amp DPDT
Omron LY2 at Amazon / Choose 120Volt coil
Surface mount socket for Omron
Relay and socket at Amazon
30 Amp DPDT relay at Amazon
40 Amp DPDT relay at Amazon
Magnecraft relay at Amazon
12 amp DPDT Packard at Amazon
Omron relay/Page 450 / pdf
How to wire and troubleshoot photoeye
Reverse photo eye
Larger image

Reverse photo eye

NC normally closed is ON during the day, and OFF at night
NO is OFF during the day and ON at night
COM is common terminal
Connect power to bottom two terminals (red and white wires)
Omron relays
120 volt Omron relay
Surface-mount DPDT 120 V Relay with socket
Photo eyes
Terminal kits

How to install terminals

Surface mount DPDT relay

In-line fuse to protect photo eye

Add 15 amp busman line fuse to black wire going to photo eye to protect device if amp load of motor exceeds photo eye maximum load rating. See illustration

Panel mount fuse holders at Amazon
Buy fuseholder at Amazon
Buy fuseholders at Amazon

Fuse blocks at Amazon
Electrical terminals
Solder guns
Buy fast and slow acting fuses:
Ceramic fuses at Amazon
Fast acting ceramic fuses

Read more about fuseholders and fuses

Wire sizes

20 amp breaker = 12 gauge wire / max 20 x 80% = 16 amps
30 amp breaker => 10 gauge wire/ max 30 x 80% = 24 amps


Select correct wire size
How to select and install wire connector

208-240 Volt photocell wiring

120Volt photo eye can control 240Volt load as long as Neutral wire is present.
Photo eye control requires Neutral wire to power the internal switch. (Or for non-code-compliant solution, connect white wire on photocell to bare ground wire)

240Volt circuit can be turned off by turning off power to either Hot1 or Hot2. This is called turning off 'one leg' in 240V circuit.

12-3 wire or 10-3 wire is needed to provide 2 hot legs and 1 neutral

Read about 240Volt circuit
ST01C timer controls 240Volt water heater
Timer has 3 wires plus green ground wire

Use timer to control any amp load using contactor

Intermatic ST01 timer at Amazon
Ei600 5-year warranty timer at Amazon
CR2 replacement battery at Amazon

Contactor with 120Volt coil At Amazon
Contactor with 240Volt coil At Amazon

Intermatic timers and manuals

Gas and electric water heaters Industrial electric at Amazon

Industrial supplies at Amazon

Industrial and scientific Amazon
Intermatic control centers Intermatic control centers:
+ manuals and parts

Including Z-wave
box timers Compare box timers

Control with Z-wave
programmable timer Compare programmable timers

Control water heater with programmable wall timer
Countdown timers Compare countdown timers

Control water heater with countdown timer
Compare power packs

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