IXOM ResidualHQ Use and maintenance manual
©2022 IXOM Watercare Inc. | www.ixomwatercare.com | 866 - 437 - 8076 | [email protected]©2022 IXOM Watercare Inc. | www.ixomwatercare.com | 866 - 437 - 8076 | [email protected]
ControlManual_ResidualHQ_10380_20220809a
ResidualHQ
Control Manual
Table of Contents
10014_20220110
ResidualHQ
Control Manual
Safety 1
Getting Started 4
Menu Layout 6
Menus - Monitor 7
Menus - Operation 8
Menus - Configuration 10
Menus - Administration 13
Initial Settings 14
Modbus Communication 20
Modbus Registers 21
Datalogging 27
Troubleshooting 28
ControlManual_ResidualHQ_10380_20220809a
Carefully read safety information when you see
any safety symbols.
Be sure you have read all installation, operation, maintenance and safety instructions
before you install, service or begin to operate this unit.
Accidents occur every year because of careless use of industrial equipment. You can avoid
hazards by following these safety instructions, and applying some ordinary common sense
when operating or servicing this unit.
Keep in mind that full operator attention and alertness are required when operating or
servicing this unit.
USE COMMON SENSE!! Most accidents can be avoided by using common sense and
concentration on the job being done.
Safety
Safety
10394_20220119 ControlManual_ResidualHQ_10380_20220809a - 1
IMPORTANT!!!
Follow all federal and state laws in regards to
safety regulations of working at heights, conned
spaces, rescue, etc. as required by the U.S.
Department of Labor, Occupational Safety and
Health Administration. Use necessary PPE when
placing and servicing this unit.
Identify all possible hazards. Determine what
safeguards are needed and implement them.
Only you, the user, understand your product
and system characteristics fully. The ultimate
responsibility for safety is with you. Your
safety ultimately rests in your hands. Do your
part and you will enjoy safe, trouble free operation
for years to come. This instruction manual is not
intended to include a comprehensive listing of all
details for all procedures required for placement,
operation and maintenance. If you have a
question about a procedure or are uncertain
about any detail, Do Not Proceed. Please
contact GridBee Customer Service at
866-437-8076 to speak to a representative.
Electrical Hazard
WARNING: THIS EQUIPMENT CONTAINS
HIGH VOLTAGE! ELECTRICAL SHOCK CAN
CAUSE SERIOUS OR FATAL INJURY. ONLY
QUALIFIED PERSONNEL SHOULD ATTEMPT
PLACEMENT, OPERATION AND MAINTENANCE
OF ELECTRICAL EQUIPMENT. REMOVE ALL
SOURCES OF ELECTRICAL POWER BEFORE
PERFORMING ANY SERVICE WORK TO THE
MACHINE. USE PROPER LOCKOUT TAGOUT
(LOTO) PROCEDURES TO ENSURE A SAFE
WORK ENVIRONMENT.
Rotating Hazard
CAUTION: KEEP BODY APPENANDAGES OR
LOOSE CLOTHING AWAY FROM EQUIPMENT
WHILE OPERATING. ENSURE EQUIPMENT IS
OFF BEFORE ATTEMPTING SERVICE.
Entanglement Hazard
WARNING: ENSURE THAT PERSONNEL ARE
CLEAR OF THE ELECTRIC CORD AND CHAIN TO
AVOID ENTANGLEMENT.
Chemical Hazard
WARNING: HIGHLY FLAMMABLE LIQUID AND
VAPOR. CAUSES MILD SKIN IRRITATION. CAN
CAUSE SERIOUS EYE IRRITATION. KEEP
AWAY FROM HEAT/SPARKS/OPEN FLAME. NO
SMOKING. AVOID BREATHING VAPORS. USE IN
WELL VENTILATED AREA. WEAR PROTECTIVE
GLOVES. DO NOT EAT, DRINK OR SMOKE WHEN
USING. WASH HANDS THOUROUGHLY AFTER
HANDLING.
Laceration Hazard
CAUTION: EDGES MAY BE SHARP AND CAUSE
LACERATION IF PROPER CARE IS NOT USED.
Safety
Safety
10394_20220119 ControlManual_ResidualHQ_10380_20220809a - 2
Permit-Required
Conned Spaces
A conned space has limited openings for
entry or exit, is large enough for entering and
working, and is not designed for continuous
worker occupancy. Conned spaces include
underground reservoirs, ground storage tanks,
elevated tanks, silos, manholes, and pipelines.
Conned Space Tips
• Do not enter permit-required conned spaces
without being trained and without having a
permit to enter.
•Review, understand and follow employer’s
procedures before entering permit-required
conned spaces and know how and when
to exit.
•Before entry, identify any physical hazards.
•Before and during entry, test and monitor for
oxygen content, ammability, toxicity or
explosive hazards as necessary.
•Use fall protection, rescue, air monitoring,
ventilation, lighting and communication
equipment according to entry procedures.
•Maintain contact at all times with a trained
attendant either visually, via phone, or by
two-way radio. This monitoring system
enables the attendant and entry supervisor
to order you to evacuate and to alert
appropriately trained rescue personnel to
rescue entrants when needed.
Refer to 29 CFR 1910.146 for complete
regulations set by OSHA. Refer to your state's
regulations if your state established and operates
their own safety and health programs approved
by OSHA.
Protect Yourself
It is important that you comply with all relative
OSHA and local regulations while installing
and performing any maintenance to the mixer
circulation equipment.
Key OSHA Compliance Standards that must
be followed (and not limited to) are:
• 1910.146 Permit-required conned spaces
• 1910.147 Lockout/Tagout
• 1926.500 Fall Protection
Fall Protection Tips
•Identify all potential tripping and fall hazards
before work starts.
•Look for fall hazards such as unprotected
oor openings/edges, shafts, open hatches,
stairwells, and roof openings/edges.
•Inspect fall protection and rescue equipment
for defects before use.
•Select, wear, and use fall protection and
rescue equipment appropriate for the task.
•Secure and stabilize all ladders before
climbing.
•Never stand on the top rung/step of a ladder.
•Use handrails when you go up or down stairs.
•Practice good housekeeping. Keep cords,
welding leads and air hoses out of walkways
or adjacent work areas.
Refer to 29 CFR 1926.500 for complete
regulations set by OSHA. Refer to your state's
regulations if your state established and operates
their own safety and health programs approved by
OSHA.
Lockout Tagout
When the On/O switch is in the "ON" position,
the mixer may start up at any time if not already
operating. The mixer's On/O switch can be
locked out by placing a pad lock thru the door latch
of the controller after the switch has been turned
to the "OFF" position. The On/O switch is to be
used as the emergency stop.
Safety
Safety
10394_20220119 ControlManual_ResidualHQ_10380_20220809a - 3
Navigation
Menus are traversed via touchscreen, or pushbuttons.
When graphical buttons are shown directly above tactile
pushbuttons, the two functions are identical. This is shown
in Figure 1, with subsequent traversal to the next screen in
Figure 2.
Figure 2: Next screen, no authorization
Figure 1: Welcome screen
Figure 3: Login
Figure 4: Keyboard
Access Protection
The graphic highlighted in Figure 2 is utilized throughout
the control program to log-in and access protected functions.
The system utilizes an authorization hierarchy to prevent un-
wanted tampering or control. Users are granted permissions
by a System Administrator, which may be maintained locally
to manage user proles. When the icon is selected, a log-in
dialogue is initiated as shown in Figures 3 and 4.
Authorizations
When a user is recognized, the system will grant the
appropriate access, allowing the user to perform
diering ranges of functions within the system.
1. Monitors
2. Operators
3. Congurators
4. Administrators (Full)
Getting Started
Getting Started
Navigation, Layout, and Basic Configuration
10357_20220119 ControlManual_ResidualHQ_10380_20220809a - 4
Layout
Access-protected screens (Figure 7) maintain common
features to allow for easy traversal through the user
program, as well as quick views of the current status
of the system.
The relative location within the user program is clearly
highlighted in the upper banner at the top of each screen
(Figure 6). Additionally, common navigational buttons are
located along the lower banner (Figure 8):
• Home (Logout)
• Back
• Quick Shutdown
Figure 6: Program location indication
Figure 7: Typical access-protected screen
Figure 10: Quick View
Figure 9: Parameter Input
Value Entry
In general, if a parameter is seen with a white, bounded,
background the parameter may be changed. When pressed,
a keyboard will appear (Figure 9) allowing user entry. If the
user does not have appropriate access, a log-in dialogue will
appear rst.
If the value does not appear to change once it has been
entered and conrmed, it is likely an invalid entry was made.
See Parameter Information for specic details on limits, etc.
Parameters shown without a white, bounded, background
are simple program outputs. Many of these may be
accessed via Modbus or other SCADA connections. See
Parameter Information for specic details on access,
addresses, multipliers, etc.
Figure 8: Common Navigation
Quick View
A number of indicators are given in the bottom right-
hand corner (Figure 10), allowing users to quickly identify
real-time status information such as:
• Current mode status
• Overall system status
• Mixer status
• Residual level
• Current user
• System time
Getting Started
Getting Started
Navigation, Layout, and Basic Configuration
10357_20220119 ControlManual_ResidualHQ_10380_20220809a - 5
Real-Time Values
Chlorine Residual Trend
Recent Dosing Information
Monitored Tank and Bulk Storage Levels
Alarm Log (Warnings and Errors)
Automated Management Mode Control
Manual Dosing Mode Control
Maintenance Mode Control
System Conguration
General Operation Parameters
Automated Management Parameters
Trending and Historical Data Parameters
User Administration and Runtime Control
Controller Diagnostics
Home
Login
Monitor
Operate
Congure
Administration
Navigate Back
Stop Circulation
Controller Input/Output Monitor
Menu
Menu Layout
Overview
10358_20220119 ControlManual_ResidualHQ_10380_20220809a - 6
Base ► Monitor ►Trend
Name Description
Chlorine Residual Trend Trendline of monitored residual level
Residual (ppm) Current value of monitored residual
Target (ppm) Desired residual level (Automated Management)
Base ► Monitor ► Tanks
Name Description
Tank Status Information Reads current level of Monitored Tank and Chemical Bulk Storage. Levels displayed must be above
congured limit, corresponding to LOW LVL pilot light.
Bulk Clear System monitors Chemical Bulk Storage for unaccounted usage or changes in volume. When tanks are
lled, emptied, or the volume is otherwise changed must clear the current tracking information by pressing
BULK CLEAR.
Base ► Monitor ► Real-Time
Name Description
Motor Conditions Quick view of the current status of the Mixer, Sample Pump, and Return Pump. Amperages here must be
within congured limits, corresponding to the STATUS pilot light of each. CMD signies if the respective
pump is commanded to run.
System Conditions The system is continuously monitoring a number of functions, the majority of which are represented by pilot
lights under system conditions.
Overview
Users with Monitor permissions will have access to the following screens and menus. The Monitor menus are available
to quickly view system status, historical actions, and diagnostic information. Monitor is the lowest access level, and has
limited operational and administrative capabilities.
Base ► Monitor ►Dosing
Name Description
Last Dose Information Provides relevant information on the last dose made by the system including: Date and Time, Chemical
Type, Volume(s), and the Mode in which the command was made.
Daily Volumes Current total volume(s) of respective chemical(s) dosed since 0:00 of the current day. Volume limit pilot light
indicating current daily volume in excess of congured limit.
Base ► Monitor ► Alarms
Name Description
Alarm Log Log providing diagnostic information for recognized system warnings and faults. Warnings are denoted by
a (+) and no reset is required. Faults are denoted by (!) and do require a reset (Base > Operate).
Menu
Monitor
Monitor Menu
System Status and Diagnostic Information
10349_20220119 ControlManual_ResidualHQ_10380_20220809a - 7
Base ► Operate ► Auto. Mgmt.
Name Description
Current Status Brief description of current automated action
Residual Target Desired chlorine residual level
Crossover Target Chlorine residual level where system will change from chlorine to chloramine feed
Decrease Threshold Threshold which prompts recovery action
Time Remaining Time remaining for current action. Tracks data establishment, determination wait periods, and solution
feed times.
Recovery Fault System has exceeded maximum number of attempts to recover residual level. Likely an indication of
incorrect settings. See Conguration parameters for additional information.
Breakpoint Detected System has detected a Breakpoint condition.
Chloramine Override Chloramines will exclusively be used to recover to residual setpoint
Base ► Operate ► Manual Dose
Name Description
Current Status Brief description of current manual dosing action
Flow Rate Flow rate (gallons per hour) of specied chemical
Dose Amount Volume (gallons)
Continuous Dose Continuously dose specied chemical. Will feed until Daily Volume Limit reached.
Feed Ratio Ratio of Cl2:NH3-N
Volume Remaining Volume remaining in specied manual dose
Start/Stop Start or Stop the manual dose
Chemical Selection Chemical solutions available to be manually dosed
Base ► Operate
Name Description
Mode Selection Graphical buttons allowing traversal from one mode to another. Active mode is indicated by green pilot
light. If change is not immediate, transition likely necessary. This is due to automated cleaning and ushing
mechanisms.
Mode Reset Resets all non-motor related modes of the system including valve, feed, and watchdog schemes.
Memory Reset Resets memory-related alerts and decisions (daily volumes, last dose information)
Mixer Control Switch controlling submersible tank mixer.
Circulation Control Switch controlling return pump (VFD) and sample pump. If this is commanded on while the mixer is o, the
mixer will be turned on as well.
Motor Reset Resets all motor monitoring schemes
Overview
Users with Operation permissions will have access to the following screens and menus. A more detailed description of the
specic parameters and there limits may be found in the Conguration Parameter listing. Please note that not all system
actions are allowed with Operation permissions.
Menu
Operation
Operation Menu
Parameter Information
10350_20220119 ControlManual_ResidualHQ_10380_20220809a - 8
Base ► Operate ► Maintenance Configuration
Name Description
Valve Selections Manually actuates the respective valves. This overrides the system’s built-in ushing, cleaning, and ow
detection and control schemes. Use with extreme caution.
Remote Enable Switch controlling remote control. If enabled, no Maintenance operations will be allowed. This protects the
system from being manually congured without personnel on site.
Menu
Operation
Operation Menu
Parameter Information
10350_20220119 ControlManual_ResidualHQ_10380_20220809a - 9
Overview
Users with Conguration permissions will have access to the following screens and menus. These menus should be
accessed with caution, as many settings will directly change the operation of the system in automated modes, resulting
in changes to automated decision-making processes and actions.
Base ► Configure ► System
NameName UnitsUnits Def.Def. LowLow HighHigh DescriptionDescription
Motor Current Limit % 10 0 100 Motor over/under current limit (Sample Pump and Mixer monitor)
Sample Current
Setpoint
amps 12.00 0.00 20.00 Sample Pump typical operating current setpoint
Mixer Current
Setpoint
amps 12.00 0.00 20.00 Mixer typical operating current setpoint
Chlorine Degas
Enable
T/F T Enable chlorine degassing scheme
Ammonia Degas
Enable
T/F F Enable ammonia degassing scheme
Remote Enable T/F F Enable remote control (Via Modbus RTU)
Modbus ID 1 1 256 Low level alert for bulk chlorine storage. Units and Low/High limits
user-dened.
Modbus Reload T/F F Modbus RTU reload request. Required after Modbus ID change.
Screen Timeout secs 300 0 9999 Seconds of inactivity before automatic logout
Local Log Start T/F F Start/restart local (HMI USB) datalogging
Local Log Stop T/F F Stop local (HMI USB) datalogging
Set System Time Set system (local) time. Enter value, press button to save
Fatal Fault Denition T/F F Stops sample if: Ammonia valve routine error
Fatal Fault cont’d T/F F Stops sample if: Chlorine valve routine error
Fatal Fault cont’d T/F F Stops sample if: Chemical feed routine error
Fatal Fault cont’d T/F F Stops sample if: Mixer monitoring routine error
Fatal Fault cont’d T/F F Stops sample if: Unaccounted bulk chemical change
Fatal Fault cont’d T/F F Stops sample if: Flow verication failure
Fatal Fault cont’d T/F F Stops sample if: Degassing routine error
Fatal Fault cont’d T/F F Total Chlorine readings out of range
K Factor Rinse 3785.41 K factor value for Rinse ow meter
K Factor Chlorine 3785.41 K factor value for chlorine ow meter
K factor ammonia 3785.41 K factor value for chlorine ow meter
Retry attempts 8Circulation retry attempts after a nonfatal error has occurred
Sleep Timer Minutes 10 Minutes system can be powered down before turning o circulation on
reboot
Total Chlorine Max. ppm 4.0 Alarm if total chlorine is above this value
Total Chlorine Min. ppm 0.5 Alarm if total chlorine is below this value
Remote Tank input T/F F Use customer input for tank data over modbus
Menu
Configuration
Configuration Menu
Parameter Information
10360_20220119 ControlManual_ResidualHQ_10380_20220809a - 10
Base ► Configure ► General Operation
NameName UnitsUnits Def.Def. LowLow HighHigh DescriptionDescription
Flow Rate GPH 1.00 0.00 2.50 Flow rate of the set/commanded chemical. Common setting for automated
and manual actions.
Feed Ratio 4.00 0.000 5.000 Ratio of Cl2:NH3-N. Common setting for automated and manual actions.
Ratio Factor 1.63 0.000 10.00 Ratio of (Wt. NaClO (lbs/G) * % Avail. Cl2):(Wt. LAS (lbs/G) * % Avail. N).
Common setting for automated and manual actions.
Chlorine Flow Adj. 0.800 0.000 9.999 Calibration adjustment factor [Flow = Adjust * Sensor]
Ammonia Flow Adj. 0.800 0.000 9.999 Calibration adjustment factor [Flow = Adjust * Sensor]
Actuation Change % %50.00 0.00 99.99 Minimum recognition percentage of recent valve actuations
Flow Error % %25.00 0.00 99.99 Maximum allows deviation from expected ow sum
Base ► Configure ► Automated Management
NameName UnitsUnits Def.Def. LowLow HighHigh DescriptionDescription
Data Establishment
Duration
mins 30 0 32767 Length of time system waits for trending data to stabilize prior to action
[Automated Management Mode decisions]
Action Timeout mins 1440 0 32767 If last dose was not made within this timeout duration, prior actions will not be
considered [Automated Management Mode decisions]
Feed Duration mins 4 0 32767 Feed duration before stopping to wait and see eect
[Automated Management Mode decisions]
Determination Time mins 60 0 32767 Duration of wait period after feed has been stopped before making trend or
threshold determinations [Automated Management Mode decisions]
Determination
Hysteresis
mins 5* * Number of minutes system waits before checking if threshold crossing was
false positive. Setting must be greater than the Trending Data Register
Period, and less than Conrmation Wait.
Residual Target ppm 3.00 0.00 20.00 Desired chlorine residual level. System will attempt to maintain this level while
in Automated Management Mode.
Crossover Target ppm 3.00 0.00 20.00 Chlorine residual level at which the system will change from chlorine to
chloramine during recovery to avoid overshoot and subsequent residual
destruction [Automated Management Mode]
Decrease Threshold ppm 1.00 0.00 * When residual drops below this point system will take action [Automated
Management Mode]. Setting must be less than Residual Setpoint
Recovery Threshold ppm 0.25 0.00 * When residual increases above this point system will consider setpoint
reached [Automated Management Mode]. Setting must be less than
Decrease Threshold.
Recovery Attempt
Limit
2 0 32767 Number of attempts system will make to recognize a residual increase during
recovery [Automated Management Mode]
Breakpoint Ratio 0.45 0.00 1.00 Ratio of Free Chlorine to Total Chlorine that triggers Breakpoint Detection
[Automated Management Mode]
Menu
Configuration
Configuration Menu
Parameter Information
10360_20220119 ControlManual_ResidualHQ_10380_20220809a - 11
Base ► Configure ► Trending and Historical Data
NameName UnitsUnits Def.Def. LowLow HighHigh DescriptionDescription
Trending Data
Register Period
mins 1 0 32767 Minutes between logging of trending data values
Residual Trend
Points
5 0 32767 Number of data points averaged for “recent” data
Chlorine Vol. Limit gals 12.0 000.0 330.0 Feed volume limit (24 hour period)
Ammonia Vol. Limit gals 12.0 000.0 330.0 Feed volume limit (24 hour period)
Unaccounted
Change Limit
%10.00 0.00 100.0 Unaccounted change monitor. If the bulk storage sensor reports an
unaccounted change (no dosing/reset for ll) in the set period the system
will report an error.
Unaccounted
Change Timeout
hrs 15 0 24 Unaccounted change monitor. If the bulk storage sensor reports a change
greater than the limit during this time period, the system report an error.
Low Level Chlorine ? 15 * * Low level alert for bulk chlorine storage. Units and Low/High limits
user-dened.
Low Level Ammonia ? 15 * * Low level alert for bulk chlorine storage. Units and Low/High limits
user-dened.
Low Level Monitor
Tank
? 15 * * Low level alert for monitored tank. Units and Low/High limits user-dened.
Tank Sensor Units ‘%’ User-dened String for Tank Sensor Units. Max of 4 characters.
Tank Sensor Min. ?0.0 (-) (+) User-dened Floating point low limit for Tank Sensor. Used to scale input
value (linear).
Tank Sensor Max. 100.0 (-) (+) User-dened Floating point high limit for Tank Sensor. Used to scale input
value (linear).
Bulk Chlorine Units ‘%’ User-dened String for Bulk Chlorine Storage Units. Max of 4 characters.
Bulk Chlorine Min. ?0.0 (-) (+) User-dened Floating point low limit for Bulk Chlorine Storage. Used to scale
input value (linear).
Bulk Chlorine Max. 100.0 (-) (+) User-dened Floating point high limit for Bulk Chlorine Storage. Used to scale
input value (linear).
Bulk Ammonia Units ‘%’ User-dened String for Bulk Ammonia Storage Units. Max of 4 characters.
Bulk Ammonia Min. ?0.0 (-) (+) User-dened Floating point low limit for Bulk Ammonia Storage. Used to scale
input value (linear).
Bulk Ammonia Max. 100.0 (-) (+) User-dened Floating point high limit for Bulk Ammonia Storage. Used to
scale input value (linear).
Menu
Configuration
Configuration Menu
Parameter Information
10360_20220119 ControlManual_ResidualHQ_10380_20220809a - 12
Overview
Users with Administration permissions will have access to the following screens and menus. These menus allow for user-
access control, as well as additional diagnostic and troubleshooting control relating to the PLC and HMI.
Base ► Administration ► User
Name Description
User Administration Interactive user-access control. Allows modication of user names, passwords, groups, and logo times.
Group permissions follow the format:
• PLC User (default, no edit)
• Users - Monitor screens
• Operators - Operation screens (and all Users permissions)
• Congurators - Conguration screens (and all Operators permissions)
• Commissioners - Administration screens (and all Congurator permissions)
Stop Runtime Button allowing runtime control of HMI. Pressing will allow editing of HMI-specic settings.
Online/Oine Buttons controlling connection of HMI to PLC.
Base ► Administration ► Diagnostics
Name Description
Controller Diagnostics Interactive menu allowing advanced diagnostic information from PLC to be displayed. Useful for viewing
loss of power, or other runtime events.
Stop Runtime Button allowing runtime control of HMI. Pressing will allow editing of HMI-specic settings.
Online/Oine Buttons controlling connection of HMI to PLC.
Base ► Administration ► I/O
Name Description
Digital Inputs Pilot light will illuminate RED if digital input is currently HIGH.
Pulse Counters Raw counter value of ow verication sensors. Values are updated periodically, so counts will not appear
continuous. Expected values between 0 and 10000. Useful for diagnosing ow verication issues.
Digital Outputs Pilot light will illuminate RED if digital output is commanded HIGH.
Analog Inputs Raw input values seen by the PLC corresponding to each analog input utilized. Expected values for
4-20mA sensors, 4mA = 0, 20mA = 27648. Values outside this range indicate under/overow, and may
indicate system error(s).
Menu
Administration
Administration Menu
User Access and Diagnostics
10359_20220119 ControlManual_ResidualHQ_10380_20220809a - 13
Overview
The ResidualHQ system has a profound impact on the operation of a tank requiring a systematic tuning process that pro-
vides the best opportunity for sustained disinfectant residual management. Many factors may impact operational settings,
such as initial disinfectant levels and ratios, water age, tank piping, turnover and usage, ll rates, and temperature. While
not required during routine start-up operations, the following steps should be taken upon initial placement of the equip-
ment.
Step 1 – Begin Sampling
Prior to the addition of chemical to the tank, or even mixing, the ResidualHQ should be given time to sample the water for
a suggested duration of one hour. During this time the online analyzers are given time to stabilize, and should then be cal-
ibrated, by manually measuring Total and Free Chlorine residuals. In the case of chloraminated systems, Monochloramine
and Free Ammonia tests are also benecial for more advanced tuning.
Step 2 – Begin Mixing
Once initial residual tests are concluded, the mixer(s) should be turned “ON”. The addition of an active mixer will likely
cause a temporary increase in chlorine demand, resulting in a residual decrease within the monitored tank. While not
always possible the mixer should be allowed to operate for 24 hours in order for chlorine demand to stabilize.
Step 3 - Begin Corrections
The system is loaded with default settings for Automated Management. However, at a minimum the following settings
should be conrmed prior to starting operation at a specic tank location:
• Residual Target: Desired chlorine residual level
• Decrease Threshold: Decrease in residual prior to action
• Feed Rate: Rate at which disinfectant is fed
• Feed Duration: Duration disinfectant is fed during correction
• Determination Wait Time: Length of time after the conclusion of disinfectant feed prior to analyzing result
The following pages should only be used as a guideline, and should not completely replace prior knowledge or operating
procedures, and is not intended to supersede any existing statutes or laws. A spreadsheet is available that follows the
calculations detailed below and the example found in Appendix A. Please contact Ixom Watercare, Inc. Customer Service
for more information.
Step 3.A – Chemical Calculations
In order to calculate required amounts of disinfectants, the strengths of the respective disinfectants used must be known.
Initial Settings
Initial Settings
10386_20220809 ControlManual_ResidualHQ_10380_20220809a - 14
Step 3.B – Correction Amount
In order to get baseline settings, the correction amount will be determined by the following parameters:
- Incoming Water Residual Concentrations
- Outgoing Water Residual Target
- Daily Usage or Flow (Millions of Gallons Per Day, MGD)
- Tank Volume or Size (Millions of Gallons, MG)
Since usage is generally cyclical over a 24-hour period, we dene “low turnover” as daily ows less than the tank volume.
Conversely, “high turnover” is daily ows exceeding the tank volume.
If the incoming water is generally at the Target Residual level, the Desired Increase (Eq. 3) should be equal to the residual
loss that typically occurs in the tank. The system must have the capacity to increase all water by the Desired Increase
(Eq. 3). Additional capacity is also recommended, as tank-specic factors such as usage variability, loss of residual, ll
rates, etc. may impact chlorine demand. As a starting point, 30% additional capacity may be used for many applications.
For initial settings, this daily volume should be distributed into 2-4 Corrections Per Day.
- If low turnover, or incoming water is generally “good” (close to or above target residual), less reactive dosing may
be used (lower number of corrections)
- If high turnover and incoming water has low residual, more reactive dosing will be required (higher number of
corrections)
- At this point, a check should be made to ensure the incremental correction amount is deemed acceptable by the
operator. If the amount is too high, increase the number of corrections to lower the incremental correction amount.
Once an acceptable incremental volume is found, the Feed Rate and Feed Duration (Eq. 7) may be set. For standard
units, a starting Feed Rate of 1.25 GPH may be used. This is approximately equal to 50% of the standard unit’s capacity,
and allows exibility in further tuning.
Initial Settings
Initial Settings
10386_20220809 ControlManual_ResidualHQ_10380_20220809a - 15
Step 3.C – Determination Wait Time
The Determination Wait (Eq. 8) time is the length of the time the system waits after a corrective action to determine the
outcome. Using values found in the previous step (3.B)
Step 3.D – Decrease Threshold
The Decrease Threshold (Eq. 9) is how far the system will let the monitored residual drop from the Target Residual setting
prior to beginning disinfectant feeds. For an initial value, the Residual Increase (Eq. 6) value calculated above may be
used along with a percentage of recovery.
- Chlorinated Recovery Percentage: 70-100%
o In chlorinated systems larger corrections are acceptable since we do not have to worry about additional
chemical reactions as in the case of chloraminated systems
- Chloraminated Recovery Percentage: 50-70%
o Smaller increments are benecial since the objective is to re-bind available ammonia without overshooting
and negatively impacting the existing residual levels
Step 4 - Continued Tuning
Once the system has made several corrections the Determination Wait Time should be matched to the dynamic conditions
of the tank, accounting for mixing, ll cycles, usages, etc. Adjustments should be made based on residual changes
witnessed after each corrective action. For most applications, Determination Wait Time should equal the length of time
until residuals have stabilized after the conclusion of a feed, with a minimum of 1 hour.
Since the Determination Wait Time will now be a known value based on operational conditions of the tank, it may be used
to further tune the corrective settings of the unit. At this point, Daily Volume (Eq. 4) may be updated if conditions have
changed. This will be used to determine an updated Feed Duration (Eq. 10) as a function of the matched Determination
Wait Time, as well as an updated Decrease Threshold (Eq. 9).
Initial Settings
Initial Settings
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Step 4 - Continued Tuning
The resulting settings above can also be changed by altering the Additional Capacity (Step 3.B.) and Feed Rate, or by
changing the Decrease Threshold (Eq. 9). However, during these adjustments the following must be kept in mind:
- Minimizing Determination Wait Time allows the system to be more responsive, keeping the incremental doses smaller
- Decrease Threshold does not necessarily need to be updated when the Feed Duration is updated, but doing so will
help ensure the responses are made at appropriate levels
Additional Parameters
- Recovery Threshold
o May be used to change recovery characteristics. System will stop corrections once within this amount from
the residual target, making an “acceptable recovery”. This may be used to mitigate overshoot, or decrease
sensitivity of the system. Default set at 0.1ppm, but may be adjusted based on witnessed results, feed rates
used, and mixing turnover times.
- Crossover Target
o In high-use situations where recovery time is limited a Crossover Target may be employed. Should be set
at a residual level equal to or less than the boost potential of the incoming water, as determined by manual
analysis of typical incoming free ammonia concentrations, or set below the point at which a “dip” or decrease
in residual is typically witnessed during recovery.
- Determination Hysteresis
o The length of time the system waits after crossing a threshold during recovery (Crossover Target, Residual
Target) before checking for false positive.
- Conrmation Wait
o During recovery to a target, the residual must remain above a threshold for at least this length of time to be
considered valid. If the residual drops below the Recovery Threshold in the window, the system will resume
previous corrective actions.
Initial Settings
Initial Settings
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Initial Settings
Initial Settings
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