The magnetic coil creates almost, but no quite, a dead short and pulls almost all the current available when the button is pushed. If powered directly, rather than using track power, it should be on it's own power supply.
That's why the instructions for the newer FasTrack uncouplers/control tracks specifically say not to use the 'Accessory' output on the CW-80. There's a good chance the current load would fry the output.
