Chatter on output of analog input

I have a Beckhoff BC 9000 with an analog input card and a digital output card.

I think my problem may be generic enough that it perhaps has nothing to do with specific hardware.

I want an output that is controlled by a 4-20 mA input ( Beckhoff KL3012 ) to turn on above a certain point and off below that point ... the problem is that the input card thinks the input is varying and is causing the output to chatter when it is near the setpoint.

How can I get rid of the chatter?.... I don't really care to try to get rid of the variance on the input ( if it is indeed varying ) but stop the output from chattering. Can the resolution be lessened on the card or perhaps some other programming trick? Averaging or something?

thanks

Two methods:
1) Hysteresis. Have an offset between the turn on point and turn off point, ie. Turn on at 12.4 mA, and off at 11.8mA.

2) Timers. Use an on delay and/or off delay to control the minimum amount of time the output must be on and off before changing states.

A lot of applications call for both of these methods.

Great answer. Hystersis is a very important concept to understand in real world applications. Something that doesn't come across as too important in the text books!

BTW, very childish I know...but this has to be one of the funniest titles I have seen on my IE tab bar! (See picture)