How many Incandescent Watts?

[Anonymous]

#40114

I have two circuits that I am running Christmas lights off of, one a 1000 watts and the other one at 600 watts.

How many watts will the EZSwitch30 handle?

[Anonymous]

#42487

The electrical formula is Volts * Amps = Watts. 220v * 30 amps = 6600 watts inductive according to the specs. I believe an Inductive load tend to have a higher spike at the beginning of the load so a resistive load of 120v at 1600 watts as incandescent lights should be okay. The device has two separate 120 volt circuits, each switched with a separate relay so putting the 1000 watt load on one circuit and the 600 watt load on the other would add even more reserve to the equation.

[Anonymous]

#42488

One of the things that I was concerned about is whether the relay has 2 separate 15 amps “circuits”. My thought was that it may have one relay dedicated to 15 amps and another relay for the other 15 amps. If so, when using this relay on a 110 circuit, I’d only get 15 amps x 110 volts, which equals 1650 watts. which would only barely be enough if I used one EZSwitch30 for both strings of lights.

Actually, I was going to connect two EZSwitch30’s one for 1000 Watts of lights and another EZSwitch30 to 600 Watts of Lights.

The only thing that smarthome had to offer was a 1000 Watt Dimmer, but I don’t want that hooked to an outlet because if it somehow got dimmed, it could ruin something.

The biggest problems with this plan is that it will cost $230+ and I’ve got to find a place to put the EZSwitch30 near the receptacles.

[Anonymous]

#42489

With 30 amps at 220v equal to 6600 watts, that is pulling 3300 watts through each relay. That makes each relay switching 30 amps. Of course these are max values and I don’t recommend operating anything near the max rating. Supplying the EZSwitch30 from a standard outlet, which is generally on a 15 amp breaker, you have more problems with the capability of that outlet than what the EZSwitch30 can switch. With 120V * 15 amps equal to 1800 watts. Drawing 1600 watts for the lights, along with whatever else may be on that outlet circuit, you may be at or exceeding the 15 amp capacity of that circuit. You do not need two EZSwitch30 devices.

[Anonymous]

#42490

okay, then here is a good (in my opinion) question for you:

if this smarthome 2473 switch says it can handle 15 amps, then why does it give an incandescent limit of 600 watts?

15 amps x 120 volts should equal 1800 watts.

This is the reason for my initial question on this forum. It’d be nice of the guys from simplehomenet answered their forum on weekends.

Does anyone know what Simplehomenet believes is the max amount of Incandescent watts that the EZSwitch30 can handle when hooked to a 120 volt circuit?

[Anonymous]

#42491

Sorry if my responses have added to the frustration. Just to add to the question, the online user guide on the Smarthome site lists 480 watts as the maximum incandescent load for the OutletLinc. The Smarthome user forum rarely receives a comment from Smarthome. The SimpleHomeNet user forum does receive input from the company on many occasions. However, if you want a direct answer to a question on a timely basis about the EZSwitch30, call or email SimpleHomeNet Support. For answers as to why the OutletLinc is spec’ed the way it is I think you should contact Smarthome support.

There is a Topic on the Smarthome forum that discusses the topic of resistive versus incandescent versus inductive loads. The question was raised in the context of the Smarthome OutletLinc. The discussion regarding the current drawn by incandescent loads was very informative. I always took a light bulb to be a resistive load and found that Smarthome Topic discussion to prove me wrong.

The link to that Topic is …..

http://www.techmall.com/topic.asp?TOPIC_ID=2539

[Anonymous]

#42492

For the benefit of other folks who follow these topics the EZSwitch30 is rated at 240v 30 amps inductive load, per the online specs. From the discussion on the Smarthome forum about the OutletLinc it looks like they derated a 16 amp relay to 4 amps (480 watts) for an incandescent load. Lights bulbs are a resistance load but have a much higher current draw initially when the filaments are cold. I googled the topic of resistance versus inductive load and they all say about the same thing. There are inductive loads (like pump motors) and resistance loads with incandescent lights a special case resistance load due to the varying resistance of a cold filament versus a hot filament. A relay is derated some percentage from it resistance load rating when handling an inductive load such as a pump motor and derated even further for incandescent lighting. Applying the same strategy to the relays in the EZSwitch30, derating a 30 amp relay (which might have a higher resistance load rating since the published specs say 30 amp inductive load) would take a 120v incandescent load to 7.5 amps or 900 watts per relay. In the example that started this discussion I would follow my first suggestion and put the 1000 watt load on one relay and the 600 watt load on the other but also with the previously stated concern for the total amps being drawn from what is assumed to be an outlet on a 15 amp breaker. Taking 1600 watts total, divided by 120v, gives 13.3 amps. If the outlet supplying the EZSwitch30 has anything else on that electrical circuit, it could overload a 15 amp breaker. A more conservative approach would be to supply each EZSwitch30 relay from a separate 120V 15 amp circuit, or a single 120V 20 amp circuit, using the appropriate gauge wire and split the 1600 watt incandescent load equally across the two EZSwitch30 relays.

From the online specs for the EZSwitch30…

Types of loads — Resistive or inductive (lighting, pumps, AC compressors, water heaters, etc.)

Maximum Load Current — 30 Amps @ 240V Inductive

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