Clamp
LayerClamp
Using this Modifier Layer, value ranges can be clamped at their borders. Assuming you have values from 0 to 1 but want values between 0 and 8, you would set the Maximum value to 80%. Values between 0.8 and 1 will be clamped and all will be assigned a value of 0.8.
Note that all Field lists themselves clamp values less than 0 and greater than 1 by default (this can, however, be disabled).