US 4,464,315 A · Indexing controller system and method of automatic control of cooling water tower systems

Abstract

A control system and method of controlling the cycling of water in a cooling tower system having a source of make-up water of variable conductivity. The control system apparatus includes respective probes for sensing tower water conductivity and make-up water conductivity. The probes provide signals to a controller unit. Desired cooling system water conductivity parameters are input into the controller unit. The controller unit serves to proportionally adjust the trip point at which dumping of the cooling tower water occurs based upon the sensed water conductivities and the input parameters to maintain a predetermined Langelier's number(s). Means are provided to display system conditions and to effect calibration of the system. The method entails establishing an indexing factor based upon the cooling water parameters and the desired Langelier's number(s) and using that indexing factor for adjusting the trip point.

Claims10

Dependent claims

A control system for a cooling tower having a source of make-up water having a variable conductivity from a low to a high value, said control system comprising:

(1) first means for establishing the maximum conductivity of said low conductivity water in said tower at a predetermined Langelier's Number,
(2) second means for establishing a multiplier value based on said variable make-up waters and tower waters conductivities,
(3) third means to measure tower water conductivity,
(4) fourth means to measure make-up water conductivity,
(5) fifth means to calculate the difference between the low conductivity make-up water conductivity and measured make-up water conductivity to establish a baseline value,
(6) sixth means to multiply said baseline value by said multiplier to establish a delta value indicative of the required change in tower water conductivity to maintain the predetermined Langelier's number,
(7) seventh means to add said delta value to said maximum conductivity of said low conductivity water in the tower at said predetermined Langelier's number to produce a control value for the conductivity of the tower water, thereby maintaining said predetermined Langelier's number, and
(8) eighth means responsive to said control value for controlling bleeding and replacement water in said tower to maintain said control value.

5 more elements

Dependencies are inferred from the claim text.

Indexing controller system and method of automatic control of cooling water tower systems

Life of this patent

Indexing controller system and method of automatic control of cooling water tower systems

Life of this patent

Abstract

Claims10