Instruction manual

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Cycles of Concentration is used to open the bleed valve when the ratio of the system conductivity
to the makeup water conductivity exceeds the programmed value. Choose the option that matches
the number of makeup water sources that you will have (up to 3). The option with one makeup
source may be selected without a makeup water sensor installed if the conductivity of the makeup
water is consistent enough for a manual entry of the value. The 2 and 3 makeup water source
options can only be used if conductivity sensors are installed in both the cooling tower water and
the makeup water.
The controller recognizes the current makeup water source by comparing the makeup conductivity
to the range of values that you set up. Each makeup source can have its own cycles set point, dead
band, high alarm and low alarm. When the conductivity of the makeup water changes to a different
source, the controller does not change to the new set point values immediately, but uses the
Retention Time to transition gradually from one source’s set points to the other over the course of
the retention time.
Other (4-20 mA input 4) is used to control the bleed relay based upon a signal from a transmitter
that is connected to 4-20 mA input number 4. This option is only possible if your controller is
equipped with the analog input option card.
If you change the Type of Bleed on this page, click on the Submit button at the bottom of the page
in order to see all of the applicable menus.
Bleed Status
This menu is for information only, and displays whether the bleed output is “Off” or “On” and if
on, for how much time, as well as any alarm conditions. Possible status messages are; Off,
Off/Bio1 or 2 Lockout, Off/Dispersant Add, Off/Manual, On/Time counting up (for bleed based
on conductivity), On/Time counting up/Pre Bleed (for conductivity based pre-bleed), On/Time
counting down /Pre Bleed (for time based pre-bleed), or On/Time counting down/Hand (for
manual relay activation). Possible error messages are Timeout, No Flow, and Interlock. See
section 8.1 for a complete description of error messages.
Reset Timeout
There is also a button called “Reset Timeout” which is used to reset the output if it has been
activated for longer than the time limit imposed in the “Bleed Time Limit” menu described below.
Custom Name
This menu allows you to rename the output if desired. Type the new name into the text box.
System Conductivity
This menu is for information only, and displays the current reading from the system conductivity
electrode.
Makeup Conductivity
This menu is for information only, and displays the current reading from the makeup conductivity
electrode.
If no makeup conductivity sensor is installed, this menu allows you to manually enter the makeup
conductivity.