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Bypassing photocell on a outdoor remote switchbox?

I recently bought one of these Heath/Zenith remote control outdoor light/appliance switches to control some high intensity (disco) lights in my house. I didn't realize the switch "defaulted" to dusk/dawn operation via a photocell. The switch also supports a remote control on/off. You can also turn the dusk/dawn feature OFF via remote ... but will default back to ON in the event of a power failure. I do not want the unit turning on by itself.

So, for lack of a better idea I simply removed the photocell from the circuit. The box appears to work! It's a little weird after initial powerup as I have to click the remote a few times but then it appears to function as normal. Throwing the breaker a few times did not cause the unit to turn on (the behavior I was trying to avoid).

So, my question : Is this safe? Should I have replaced the photocell with a resistor with this type of device? My only goal in this project is a remote switch that will NOT unexpectedly turn on and of course not overheat/etc. I had to turn to this type of switch because NONE of the X10 type switches will work properly with these lights. Hard wiring a switch would be quite difficult due to the location of the lights and the fact it's old work. TIA for any opinions.

Reply to
TwoBearCatz
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It should be safe. If the photocell is CdS, then you have replaced it with an infinite resistance, which would be equivalent to a CdS cell in totally absolute darkness with no leakage.

There is certainly no danger from replacing either a CdS or a silicon photocell with an open circuit. They are not power-handling elements.

Reply to
mc

Thanks for the quick reply! I was thinking the same thing you were ... but (call me stupid) the fact that the circuit was designed to turn ON in darkness (resistance) bugged me. What do you suppose this circuit is doing now?

Reply to
TwoBearCatz

If you changed a CdS photocell to an open circuit, it should think it's in darkness now. You say it's not doing so?

Is a circuit diagram available?

Reply to
mc

If the control is properly designed then it defaults to dusk/dawn operation in the absence of a remote command where absence is defined by initial start-up and possibly after a timeout period since receipt of last command. The CdS is a light-dependent resistor with high resistance in darkness and low resistance in light. If you want the control to default to lights off then you obviously need to replace the CdS with a resistance indicating daylight. Take an ohmmeter and measure the CdS resistance in bright light. Install a fixed resistor of this value in place of the CdS. Power the control up and measure the voltage across the resistor with a voltmeter. Then compute V^2/R as the power dissipation and verify that it is < 1/2 the rating of your resistor, a

1/4W will most likely be okay.
Reply to
Fred Bloggs

You mentioned that you had to press the remote button more than once - The light is probably supposed to be "on", because it thinks it's dark out, but the remote overrides that. I had a PIR patio light with an override feature - turn the switch on, then off and on again within about a second, and it comes on steady regardless of the outside light level; you could be seeing the same or a similar effect to that.

Good Luck! Rich

Reply to
Rich Grise

Reply to
TwoBearCatz

On Fri, 09 Jun 2006 08:38:54 -0700, TwoBearCatz top-posted:

Yes, if it works, don't fix it. If it's doing what you want to do, and there is no smoke, then leave it the way it is, and don't worry about it. If it fails in the future, then the diagnosis should tell you how to do the next one. :-)

Meanwhile, you could learn to bottom-post.

Good Luck! Rich

Reply to
Rich Grise

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