# Old Style Air Wire decoders.



## John J (Dec 29, 2007)

How many amps can the old style Air Wire decoders handle?


----------



## Greg Elmassian (Jan 3, 2008)

Well, they say 10 amps, but that is at 12 volts as I understand from reading documents and talking to installers. 

Good enough for 2 locos and many have run 3 from one unit. 

The only "gotcha" is that they fry immediately if you hook power to it backwards. 

Regards, Greg


----------



## John J (Dec 29, 2007)

Hey Greg I did that once at Marty's Had to buy a old remote unit Stan had for sale just so I could run trains.


----------



## Bill Swindell (Jan 2, 2008)

The AirWire decoder is rated at 120 watts.

Volts Amps

12 10
14.4 8.2
18 6.6
20 6


----------



## Greg Elmassian (Jan 3, 2008)

It's funny how many people I have argued with when they expect 10 amps at 20 volts... 

Thanks for the chart Bill! 

Greg


----------



## John J (Dec 29, 2007)

The Higher the Voltage the less current the decoder can handle?


----------



## TonyWalsham (Jan 2, 2008)

Yes. 
AirWire rate their equipment honestly.
Perhaps other well known brands will do so one day as well.


----------



## Greg Elmassian (Jan 3, 2008)

Ratting in wattage gives the complete story. Unfortunately, it also requires some customer education, since most people fixate on the amperage only. 

Once you realize that the major limiting factor in power electronics is heat, and handling it, then wattage as the limit makes a lot of sense, like a 1200 watt blow dryer.... 

In DCC watts are volts times amps, so you see clearly that the power handling of the unit is affected by BOTH amps and volts. 

Regards, Greg 

p.s. a big heatsink does not always mean more power handling capability


----------

