Z-Wave switch Load Rating Values Question

(David P.) #1

Looking over the various GE Z-Wave (Jasco) switches I keep seeing something like the following listed and I wanted to know why Incandescent VS LED/CFL made a difference for Max Load? When is a Load not a load ? :smiley:

This is for the GE ZWave 12729 Dimmer:
Max Load 600W Incandescent
Max Load 150W Dimmable CFL/LED


Physics. :sunglasses:

An LED draws differently than an incandescent. This affects max load.

Maximum Loads
Dimmers also have maximum load requirements to ensure the load does not exceed the dimmer’s design limits. Surpassing these limits can result in premature dimmer failure, flickering due to noise, as well as breaker tripping. One of the main reasons dimmers have maximum loads is because of the inrush current caused by LED drivers. Inrush current is input current of short duration during initial start-up that exceeds the steady-state current value. The graph above shows the current waveform when a device is powered up.

Because of this inrush current, an LED may be rated as 25W but the actual wattage initially going through the dimmer is much higher. This means that if an incandescent dimmer is rated at 600W, you can’t assume you can use twenty-four 25W LED fixtures. A good rule of thumb is to allow 100W for each LED fixture so in this case, the 600W dimmer can handle only six LED fixtures.


The exact calculations vary for different reasons, but the best thing is just to take the manufacturer’s word for it with regard to any individual specification. :sunglasses:

Status of Light Switches with SmartThings
(David P.) #3


These smart bulbs are really my first use of LED bulbs so I wasnt sure.

I also noted that my GE Fan switch says max load 1.5 Amps. Do fans really only draw that low an amperage? I would have expected more.


That would be the high-end for most residential ceiling fans in the US.

There are some really big fans that do run higher so always check the specs for each individual installation.