460i/460TC Control System
Operation and Maintenance Manual
460i ELECTRONIC DEMAND SYSTEM
The 460i electronic demand system is available as an option
on automatic controls for water conditioning equipment.
Retrofitting of existing water treatment installations is easily
accomplished, and the cost is amortized over a short period of
time by the home owner in salt and water savings.
The two key components of the 460i electronic demand system
are the microprocessor, a miniature computer located on the
circuit board, and a water meter located at the valve outlet.
The flow of conditioned water through the meter generates
electrical impulses that tell the computer the amount of water
being used.
Every day, at 2:00 a.m., the past seven days' water usage is
statistically averaged to anticipate the amount of water to be
used the next day. The computer then determines if the water
conditioner has enough remaining capacity to supply the next
day's needs. If not, the unit will regenerate.
If the water usage pattern changes, the computer automatically
compensates for the change and regenerates only when
needed. This results in higher operating efficiency and lower
salt usage than a conventional conditioner operating on a fixed
regeneration schedule.
SPECIAL FEATURES 460i
Memory Retention
During a power outage, all of the data in the microprocessor's
memory is stored in a special electronic chip called NOVRAM,
Nonvolatile Random Access Memory. This data includes the
time of day, water usage amounts, and the number of days
since the last regeneration. The NOVRAM will maintain the
data in its memory. When power is restored, the NOVRAM
returns the data to the microprocessor and operation resumes
as if an outage never occurred.
The time of day will be late by the length of the power
outage. Most power outages are less than one minute in
duration. Therefore, it may be months or years before the
time display would require resetting. If an outage of one or
more hours occurs, the time of day should be reset. No other
reprogramming is necessary.
Self-Adjusting Reserve
"Reserve" refers to the amount of soft water that may be
needed for the next 24 hours. The microprocessor calculates
how much soft water was used and adjusts the reserve
capacity accordingly at the end of each day. As a result, the
reserve is kept at a minimum for optimum economy. The
reserve amount is calculated by multiplying the average past
seven days' usage by 1.20. Regeneration decisions are based
on the calculated reserve.
In the event of unusually high water usage (twice or more than
the current daily average), the high usage amount will be used
as the reserve when the computer performs its regeneration
computation at 2:00 a.m. This is done in anticipation of a
second day of very high usage.
High Water Usage
The 460i is programmed to react to a sudden increase in
water usage. If a day's usage is more than double the current
average, the computer anticipates that a second day of
high usage is likely to occur. The high usage amount will be
used as the reserve when the 460i performs its regeneration
computation.
Low or No Water Usage
The 460i is programmed to recognize a day of very little or no
water usage as an abnormality. It will not use data from such a
day to compute the average usage. For example, if the family
is on vacation for a week, the prior average will be maintained.
When household activity resumes, the 460i will operate as if
the vacation had not occurred.
Design Reliability
Solid-state electronics assure many years of trouble-free
performance. And, the metering system has only one moving
part, that is the rotating turbine that measures water usage and
creates magnetic pulses that are continually counted by the
microprocessor to determine the need to regenerate.
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