This is the most inefficient of all single cylinder water softeners.
A time controlled water softener operates on a time clock set by the homeowner or plumber. This means the softener will regenerate (cleanse itself), at the same time every day or two, whether it needs to be cleaned or not.
If you use more soft water than is available, the softener will be unable to supply it, and hard water will pass to service until its next pre-set regeneration.
Timer controlled water softeners are always more wasteful on water and salt, and will therefore cost much more to run.