Edelbrock electric choke

when i turn the key to the on position the position right before u get ready to crank the engine, my choke activates and starts to open. is this sapposed to happen. i thought it was sappposed to open from the engine temp. i didnt even start the car yet, i had the key to the on position so my doughter could watch the tv while i worked on my car. (81 chevy malibu 350)

You should always put the key in the accessory position. Besides heating the choke (and yes this is the way it is supposed to work), you also power the coil and may damage it.
Use the run position only when the engine is running.

Connect the electric choke to the stator wire of the alternator.

Yes, this is the way electric chokes work. When the ignition switch is ‘on’ the battery power is applied to the choke heating element. This allows the carburator to work on an engine that does not have exhaust plumbing to the give warmed air to the choke element i.e. after market intake manifolds that do not have crossunder passages between the heads.