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Photo sensitive switch

Phychotron

Phychotron

Member
I want to run my exhaust fan on high in the day and low at night. Because of humidity I want it on all night and not kicking on and off all night while I'm sleeping. A nice low speed will keep the plants happy.

I have a C.A.P. VSC-DNe that controls the fan speed based on temperature both day and night. The problem is that it will turn the fan off and not account for the humidity building up.

My idea was to get a light-sensing switch to select between two variable speed controls that are wired to the same output. That way when the lights are on it goes through dial A, but through dial B when the lights are off.

Is there any other way to get this effect? I'm trying to save money and build a lot of the stuff myself. Its just a matter of finding the right components. I was wondering if anyone knows of a switch that is capable of doing that? SPDT ON/ON photo sensitive switch rated for 120v.

picture.php
 
BlackMarketMic

BlackMarketMic

Member
With a small relay and timer.. Have your 120 v go to the input of the relay, choose n.c. contacts for day time, and wire your blower to the n.c. contacts of the relay. Then wire a fan dimmer to the n.o. contacts of the relay set to your desired speed, and wire it to your blower, your blower will be wired in parallel to both the 120 v source and the dimmer but it can only be powered by one or the other depending on time of the day. When your timer kicks in at lights out the relay will go from n.c. to n.o. contacts and the 120 v line will be dimmed down to tbe speed you set it at. Cost : 15$ relay, 10$ dimmer and el cheapo timer under 40$ total. Much simpler to buy something that is designed for this but not necessarily cheaper...I like diy, makes you learn with hands on experience and forces your brain to use its creative juices. What gadget did you buy ?
 
BlackMarketMic

BlackMarketMic

Member
Or instead of the timer have photoresistor control the coil of the relay comes down to the same thing, personally I change more faulty photo cells then timers for some reason alot of them become defective, timer although it needs occasional adjustments is much more reliable.
 
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DocTim420

The Doctor is OUT and has moved on...
Investigate using a "DPDT" relay (double pole double throw) with 120 v coil.

These are the ones I use (very popular relay used in vending machines and are 25 amp rated). http://www.newark.com/nte-electronics/r55-11a20-120f/relay-dpdt-300vac-28vdc-25a/dp/02H7416

Attach the coil contacts (A & B) to the light timer (120 v) and the fan wires to the appropriate contacts. When the relay (lights) is "on", contacts #4 or #6 will be hot (Speed 1) and when "off", contacts #1 or #3 will be hot (Speed 2). Connect the power to the post #7 or #9.

Here is the spec sheet. http://www.farnell.com/datasheets/1913132.pdf
 
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Q

queequeg152

Active member
Veteran
stop linking stupid shit, god.

the thing i posted earlier is a simple electromechanical line voltage photocell. that's all you need.
 
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DocTim420

The Doctor is OUT and has moved on...
Queeq--your photocell idea is just part of his solution, but not what he needs. Sorry, close--but no cigar.

He wants to use the same fan but have it operate at Speed 1 when lights are ON and Speed 2 when lights are OFF. Can't do that with a simple photocell--it is either "on" or "off".

So..who is posting stupid shit now? LOL.
 
BlackMarketMic

BlackMarketMic

Member
Doc is right he needs dpdt relay hooked to his lighting timer, just forgot to mention you need to add a fan dimer on whatever contacts you choose to run at night to lower blower speed. Didn't check queequeg's link but like I said photocell and photoresistors tend to go bad sooner or later. The first link from ebay looks like shitty chinese electronic components thrown onto a printed circuit board... And the saying you get what you pay for is often true, 2.99$ lol wouldn't cost much to try it but I wouldn't expect a long life from that thing, the trim pot, thats the little dimmer on the first link is complete junk, its made of plastic and is very innacurate, I have used those alot in the breadboard electronic setups I use to do when I was taking my electronics class, after ajusting it a few time your screwdriver start eating away at the plastic. That works exactly like what me and doctim420 are describing, it's the exact same thing but made of crap components, if you look carefully you see inputs outputs little relay and cheap dimmer all the components we have just listed. Just buy components from electrical/electronics supplier and I'll tell you how to wire everything...
 
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DocTim420

The Doctor is OUT and has moved on...
Also these connectors will make it easy to install.
5128271.jpg


There are more affordable relays that are rated for 10 and 15 amps, but I prefer the durability of the 25 amp ones since the appliances/devices I control are always "on"--but at different speeds depending on the photoperiod.

Also the "single pole" relays might be a few bucks cheaper than the "double pole" ones--but having the extra set of contacts (double pole) allows the ability to control two devices through one rely (second set of fans, dehumidifier, etc). You never know what you might want to do in the future.

Good luck man!
 
Q

queequeg152

Active member
Veteran
DocTim420 said:
Queeq--your photocell idea is just part of his solution, but not what he needs. Sorry, close--but no cigar.

He wants to use the same fan but have it operate at Speed 1 when lights are ON and Speed 2 when lights are OFF. Can't do that with a simple photocell--it is either "on" or "off".

So..who is posting stupid shit now? LOL.
Click to expand...

wrong.

its spdt.

wire NO to speed one.

wire NC to speed two.

done.
 
Q

queequeg152

Active member
Veteran
BlackMarketMic said:
Doc is right he needs dpdt relay hooked to his lighting timer, just forgot to mention you need to add a fan dimer on whatever contacts you choose to run at night to lower blower speed. Didn't check queequeg's link but like I said photocell and photoresistors tend to go bad sooner or later. The first link from ebay looks like shitty chinese electronic components thrown onto a printed circuit board... And the saying you get what you pay for is often true, 2.99$ lol wouldn't cost much to try it but I wouldn't expect a long life from that thing, the trim pot, thats the little dimmer on the first link is complete junk, its made of plastic and is very innacurate, I have used those alot in the breadboard electronic setups I use to do when I was taking my electronics class, after ajusting it a few time your screwdriver start eating away at the plastic. That works exactly like what me and doctim420 are describing, it's the exact same thing but made of crap components, if you look carefully you see inputs outputs little relay and cheap dimmer all the components we have just listed. Just buy components from electrical/electronics supplier and I'll tell you how to wire everything...
Click to expand...

i use a similar tork photocell to control the exterior lighting on my house. it works fine, but yea they do not last forever... but they are simple and cheap to replace once they fail.

i like the twist lock photocells, but the photocell + the twist lock base is like 30 bucks... hence i linked the conduit mount version.

you do not need a double pole relay... douple pole is for switching both hots, or switching two loads at once.

SPDT is standard for these line votlage photocells... SPDT allows you to run the lights at night or during the day( for what ever reason).
 
Q

queequeg152

Active member
Veteran
DocTim420 said:
Nope, here is what the spec sheet says (link below):

SWITCH: SPST normally closed

But its cool, sometimes I step in it and can't believe myself either....lol.

http://www.nsiindustries.com/UserFiles/Documents/Product/LI.794.E.Photocontrol.2000.3000.Series.pdf
Click to expand...

lol fine. so find a SPDT photocell, or buy a fucking Jbox mount enclosed relay box.... not a bare cube relay that will require some random relay socket

like this:
http://www.supplyhouse.com/Function...ntact-Input-Relay-20-Amp-SPDT-Class-2-120-VAC

you can even add a delay on make/break relay module if you want.

and actually if you use one of those drycontact input relay modules... you would probably not even need power to the photocell, provided you get the right type of photocell.
 
D

DocTim420

The Doctor is OUT and has moved on...
BTW, Amazon has 5 & 10 amp relays for less than $10 and a 20 amp SPDT less than $20.

5 amp DPDT (less than $5) (WITH SOCKET): https://www.amazon.com/Electromagnetic-Relay-TOOGOO-Plug-Terminal/dp/B01EYDB09I/ref=pd_day0_328_2?_encoding=UTF8&psc=1&refRID=4FCY81DKEVJCZH704EZY

10 amp SPDT (less than $10)--stripped down version of the 20 amp relay I referred to earlier, those crimp "quick disconnect connector" will work: https://www.amazon.com/gp/product/B01E63TWKK/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=A2H10JE8UETROA

15 amp SPDT (less than $20)--again, stripped down version of the 20 amp relay & those crimp "quick disconnect connector" will work: https://www.amazon.com/gp/product/B002E7Y8B4/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=ALMOUUJX7Z10S

If it were me, given the choice of two options with about the same cost--I would select the one that is "more reliable".

BTW--no sockets required...lol. Its all good.
 
BlackMarketMic

BlackMarketMic

Member
Yeah those relays that have a on delay or off delay we're fun to play with, I remember doing some setups during my electrician course we had a control panel some on switches, and the stops/emergency mushroom buttons and jog button that would control a 3 phase motor. The teacher would give us different scenarios or different wiring diagrams and we had to wire the controls to make our motors start/stop with on/off delays, green light had to light up when motor started, red light turned on when it would stop, I came up with a way to have my motor start it would run for 20 sec then stop when it stopped, after stoping for about 10 sec it restarted but motor turned on the opposite side ran for 20 sec and stoped and the cycle kept going I spent my evening figuring out how I could do this. 2 omron timer relays and a third regular dpdt relay all working together, controls and programable automation are awesome you can do just about anything !!
 
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