Walchem W600 Series User manual

W600 Series
Water Treatment Controller
Instruction Manual
Five Boynton Road Hopping Brook Park Holliston, MA 01746 USA
TEL: [phone] FAX: [phone] WEB: www.walchem.com
W A L C H E M
IWAKI America Inc.
W600 Series Controllers

Notice
© 2014 WALCHEM, Iwaki America Incorporated (hereinafter “Walchem”)
5 Boynton Road, Holliston, MA 01746 USA
[phone]
All Rights Reserved
Printed in USA
Proprietary Material
The information and descriptions contained herein are the property of WALCHEM. Such information and
descriptions may not be copied or reproduced by any means, or disseminated or distributed without the
express prior written permission of WALCHEM, 5 Boynton Road, Holliston, MA 01746.
This document is for information purposes only and is subject to change without notice.
Statement of Limited Warranty
WALCHEM warrants equipment of its manufacture, and bearing its identification to be free from defects in
workmanship and material for a period of 24 months for electronics and 12 months for mechanical parts and
electrodes from date of delivery from the factory or authorized distributor under normal use and service and
otherwise when such equipment is used in accordance with instructions furnished by WALCHEM and for the
purposes disclosed in writing at the time of purchase, if any. WALCHEM's liability under this warranty shall
be limited to replacement or repair, F.O.B. Holliston, MA U.S.A. of any defective equipment or part which,
having been returned to WALCHEM, transportation charges prepaid, has been inspected and determined by
WALCHEM to be defective. Replaceable elastomeric parts and glass components are expendable and are
not covered by any warranty.
THIS WARRANTY IS IN LIEU OF ANY OTHER WARRANTY, EITHER EXPRESS OR IMPLIED, AS TO
DESCRIPTION, QUALITY, MERCHANTABILITY, FITNESS FOR ANY PARTICULAR PURPOSE OR USE,
OR ANY OTHER MATTER.
180600 Rev. B
December 2014

TableofContents
1.0INTRODUCTION.....................................................................................................................2
2.0SPECIFICATIONS...................................................................................................................3
2.1..........Measurement Performance............................................................................................................3
2.2..........Electrical: Input/Output ...................................................................................................................4
2.3..........Mechanical......................................................................................................................................5
2.4..........Variables and their Limits ...............................................................................................................5
3.0UNPACKING & INSTALLATION .............................................................................................7
3.1..........Unpacking the unit..........................................................................................................................7
3.2..........Mounting the electronic enclosure..................................................................................................7
3.3..........Sensor Installation..........................................................................................................................7
3.4..........Icon Definitions .............................................................................................................................11
3.5..........Electrical installation .....................................................................................................................11
4.0FUNCTION OVERVIEW........................................................................................................29
4.1..........Front Panel ...................................................................................................................................29
4.2..........Touchscreen.................................................................................................................................29
4.3..........Icons .........................................................................................................................................30
4.4..........Startup .........................................................................................................................................32
4.5..........Shut Down ....................................................................................................................................36
5.0OPERATION USING THE TOUCHSCREEN........................................................................37
5.1..........Alarms Menu.................................................................................................................................37
5.2..........Inputs Menu .................................................................................................................................37
5.2.1Contacting Conductivity.............................................................................................................................. 40
5.2.2Electrodeless Conductivity ..........................................................................................................................40
5.2.3Temperature ................................................................................................................................................41
5.2.4pH................................................................................................................................................................41
5.2.5ORP.............................................................................................................................................................41
5.2.6Disinfection..................................................................................................................................................42
5.2.7Analog Input................................................................................................................................................ 42
5.2.8DI State........................................................................................................................................................42
5.2.9Flow Meter, Contactor Type........................................................................................................................43
5.2.10Flow Meter, Paddlewheel Type...................................................................................................................43
5.3..........Outputs Menu .............................................................................................................................44
5.3.1Relay, Any Control Mode ............................................................................................................................ 44
5.3.2Relay, On/Off Control Mode........................................................................................................................44
5.3.3Relay, Flow Timer Control Mode................................................................................................................ 45
5.3.4Relay, Bleed and Feed Control Mode.......................................................................................................... 45
5.3.5Relay, Bleed then Feed Control Mode.........................................................................................................46
5.3.6Relay, Percent Timer Control Mode............................................................................................................46
5.3.7Relay, Biocide Timer Control Mode............................................................................................................46
5.3.8Relay, Alarm Output Mode.......................................................................................................................... 48
5.3.9Relay, Time Proportional Control Mode.....................................................................................................49
5.3.10Relay, Intermittent Sampling Control Mode................................................................................................ 49
5.3.11Relay or Analog Output, Manual Mode.......................................................................................................50
5.3.12Relay, Pulse Proportional Control Mode....................................................................................................50
5.3.13Relay, Dual Set Point Mode.........................................................................................................................51
5.3.14Relay, Timer Control Mode.........................................................................................................................51
5.3.15Analog Output, Retransmit Mode................................................................................................................53
5.3.16Analog Output, Proportional Control Mode ...............................................................................................53
5.4..........Configuration Menu ....................................................................................................................54
5.4.1Global Settings ............................................................................................................................................54
5.4.2Security Settings ..........................................................................................................................................54
5.4.3Network Settings..........................................................................................................................................55
5.4.4Network Details........................................................................................................................................... 55

5.4.5Display Settings...........................................................................................................................................55
5.4.6File Utilities................................................................................................................................................. 56
5.4.7Controller Details........................................................................................................................................ 57
5.5..........HOA Menu....................................................................................................................................58
5.6..........Graph Menu ................................................................................................................................58
6.0OPERATION USING ETHERNET.........................................................................................59
6.1..........Connecting to a LAN.....................................................................................................................59
6.2..........Connecting Directly to a Computer...............................................................................................60
6.3..........Navigating the web pages ............................................................................................................60
7.0MAINTENANCE.....................................................................................................................61
7.1..........Electrode Cleaning .......................................................................................................................61
7.2..........Replacing the Fuse Protecting Powered Relays..........................................................................62
8.0TROUBLESHOOTING...........................................................................................................62
8.1..........Calibration Failure.........................................................................................................................62
8.1.1 Contacting Conductivity Sensors .................................................................................................................62
8.1.2 Electrodeless Conductivity Sensors..............................................................................................................63
8.1.3 pH Sensors....................................................................................................................................................63
8.1.4 ORP Sensors................................................................................................................................................. 63
8.1.5 Disinfection Sensors.....................................................................................................................................64
8.1.6 Analog Inputs ............................................................................................................................................... 64
8.1.7 Temperature Sensors....................................................................................................................................64
8.2..........Alarm Messages...........................................................................................................................65
8.3..........Procedure for Evaluation of Conductivity Electrode.....................................................................68
8.4 ........Procedure for evaluation of the pH/ORP electrode...................................................................... 68
8.5 ........Diagnostic Lights ..........................................................................................................................69
9.0SPARE PARTS IDENTIFICATION........................................................................................70
10.0SERVICE POLICY.................................................................................................................84

2
1.0 INTRODUCTION
The Walchem W600 Series controllers offer a high level of flexibility in controlling water treatment
applications.
One or two sensor inputs are available that are compatible with a variety of sensors:
Contacting conductivity
Electrodeless conductivity
pH
ORP
Any Walchem disinfection sensor
An analog (4-20 mA) sensor input card with two input circuits is also available for use with 2, 3 or 4-
wire transmitters.
Six relay outputs may be set to a variety of control modes:
On/Off set point control
Time Proportional control
Pulse Proportional Control (requires pulse output relay option)
Dual set point
Timer
Bleed or Feed based on a Water Contactor or Paddlewheel flow meter input
Cycles of Concentration
Feed and Bleed
Feed and Bleed with Lockout
Feed as a percent of Bleed
Feed as a percent of elapsed time
Daily, Weekly, 2-week or 4-week Biocide timers with pre-bleed and post-add lockout of
bleed
Intermittent sampling for boilers with proportional blowdown, controlling on a trapped
sample
Always on unless interlocked
Diagnostic Alarm triggered by:
High or Low sensor reading
No Flow
Relay output timeout
Sensor error
An option card with two isolated analog outputs may be installed to retransmit sensor input signals to
a chart recorder, datalogger, PLC or other device. They may also be connected to valves, actuators or
metering pumps for linear proportional control.
An Ethernet option provides remote access to the controller’s programming via a PC connected
directly, via a local area network, or via Walchem’s VTouch account management server.
Our USB features provide the ability to upgrade the software in the controller to the latest version.
The Config file feature allows you to save all the set points from a controller onto a USB flash disk,
and then import them into another controller, making the programming of multiple controllers fast
and easy. The data logging feature allows you to save the sensor readings and relay activation events
to a USB flash disk.

3
2.0 SPECIFICATIONS
2.1 Measurement Performance
0.01 Cell Contacting Conductivity
Range 0-300 µS/cm
Resolution 0.01 µS/cm, 0.0001 mS/cm, 0.001 mS/m, 0.0001 S/m, 0.01 ppm
Accuracy ± 1% of reading
0.1 Cell Contacting Conductivity
Range 0-3,000 µS/cm
Resolution 0.1 µS/cm, 0.0001 mS/cm, 0.01 mS/m, 0.0001 S/m, 0.1 ppm
Accuracy ± 1% of reading
1.0 Cell Contacting Conductivity
Range 0-30,000 µS/cm
Resolution 1 µS/cm, 0.001 mS/cm, 0.1 mS/m, 0.0001 S/m, 1 ppm
Accuracy ± 1% of reading
10.0 Cell Contacting Conductivity
Range 0-300,000 µS/cm
Resolution 10 µS/cm, 0.01 mS/cm, 1 mS/m, 0.001 S/m, 10 ppm
Accuracy ± 1% of reading
pH ORP
Range -2 to 16 pH units
Resolution 0.01 pH units
Accuracy ± 0.01% of reading
Range -1500 to 1500 mV
Resolution 0.1 mV
Accuracy ± 1 mV
Disinfection Sensors
Range (mV) -2000 to 1500 mV Range (ppm) 0-2 ppm to 0-20,000 ppm
Resolution (mV) 0.1 mV Resolution (ppm) Varies with range and slope
Accuracy (mV) ± 1 mV Accuracy (ppm) Varies with range and slope
Temperature Analog (4-20 mA)
Range 23 to 500°F (-5 to 260°C) Range 0 to 22 mA
Resolution 0.1°F (0.1°C) Resolution 0.01 mA
Accuracy ± 1% of reading Accuracy ± 0.5% of reading
Electrodeless Conductivity
Ranges Resolution Accuracy
500-12,000 µS/cm 1 µS/cm, 0.01 mS/cm, 0.1 mS/m, 0.001 S/m, 1 ppm ± 1% of reading
3,000-40,000 µS/cm 1 µS/cm, 0.01 mS/cm, 0.1 mS/m, 0.001 S/m, 1 ppm ± 1% of reading
10,000-150,000 µS/cm 10 µS/cm, 0.1 mS/cm, 1 mS/m, 0.01 S/m, 10 ppm ± 1% of reading
50,000-500,000 µS/cm 10 µS/cm, 0.1 mS/cm, 1 mS/m, 0.01 S/m, 10 ppm ± 1% of reading
200,000-2,000,000 µS/cm 100 µS/cm, 0.1 mS/cm, 1 mS/m, 0.1 S/m, 100 ppm ± 1% of reading
Temperature °C Range Multiplier Temperature °C Range Multiplier
0 181.3 80 43.5
10 139.9 90 39.2
15 124.2 100 35.7
20 111.1 110 32.8
25 100.0 120 30.4
30 90.6 130 28.5
35 82.5 140 26.9
40 75.5 150 25.5
50 64.3 160 24.4
60 55.6 170 23.6
70 48.9 180 22.9
Note: Conductivity ranges above apply at 25°C. At higher temperatures, the range is reduced per the range multiplier chart.

4
2.2 Electrical: Input/Output
Input Power
100 to 240 VAC, 50 or 60 Hz, 7 A maximum
Fuse: 6.3 A
Inputs
Sensor Input Signals (0, 1 or 2 depending on model code)
Contacting Conductivity 0.01, 0.1, 1.0, or 10.0 cell constant OR
Electrodeless Conductivity OR
Disinfection OR
Amplified pH or ORP Requires a preamplified signal. Walchem WEL or WDS series recommended.
±5VDC power available for external preamps.
Each sensor input card contains a temperature input
Temperature 100 or 1000 ohm RTD, 10K or 100K Thermistor
Analog (4-20 mA) Sensor Input (0, 2 or 4 depending on model code)
2-wire loop powered or self-powered transmitters supported
3 or 4 –wire transmitters supported
Each sensor input board has two channels
Channel 1, 130 ohm input resistance
Channel 2, 280 ohm input resistance
Available Power Two independent isolated 24 VDC ± 15% supplies per board
1.5 W maximum for each channel
2W (83 mA at 24 VDC) total power consumption for all channels
(four total channels if two boards are installed; 2W is equivalent to
2 Little Dipper sensors)
Digital Input Signals (6):
State-Type Digital Inputs Electrical: Optically isolated and providing an electrically isolated
9V power with a nominal 2.3mA current when the digital input
switch is closed
Typical response time: < 2 seconds
Devices supported: Any isolated dry contact (i.e. relay, reed
switch)
Types: Interlock
Low Speed Counter-Type
Digital Inputs
Electrical: Optically isolated and providing an electrically isolated
9V power with a nominal 2.3mA current when the digital input
switch is closed 0-10 Hz, 50 msec minimum width
Devices supported: Any device with isolated open drain, open
collector, transistor or reed switch
Types: Contacting Flowmeter
High Speed Counter-Type
Digital Inputs
Electrical: Optically isolated and providing an electrically isolated
9V power with a nominal 2.3mA current when the digital input
switch is closed, 0-250 Hz, 1.25 msec minimum width
Devices supported: Any device with isolated open drain, open
collector, transistor or reed switch
Types: Paddlewheel Flowmeter
Outputs
Powered mechanical relays (0 or 6 depending on model code):
Pre-powered on circuit board switching line voltage
6 A (resistive), 1/8 HP (93 W)
All six relays are fused together as one group, total current for this
group must not exceed 6A
Dry contact mechanical relays (0, 2 or4 depending on model code):
6 A (resistive), 1/8 HP (93 W)
Dry contact relays are not fuse protected
Pulse Outputs (0, 2 or4 depending on model code):
Opto-isolated, Solid State Relay
200mA, 40 VDC Max.
VLOWMAX = 0.05V @ 18 mA
4 - 20 mA (0 or 2) Internally powered
Fully isolated
600 Ohm max resistive load
Resolution 0.0015% of span
Accuracy ± 0.5% of reading

5
Ethernet 10/100 802.3-2005
Auto MDIX support
Auto Negotiation
Agency Approvals
Safety UL 61010-1:2012 3rd Ed.
CSA C22.2 No. 61010-1:2012 3rd Ed.
IEC 61010-1:2010 3rd Ed.
EN 61010-1:2010 3rd Ed.
EMC IEC 61326-1:2005
EN 61326-1:2006
Note: For EN61000-4-6, EN61000-4-3 the controller met performance criteria B.
*Class A equipment: Equipment suitable for use in establishments other than domestic, and those directly
connected to a low voltage (100-240 VAC) power supply network which supplies buildings used for
domestic purposes.
2.3 Mechanical Enclosure Material Polycarbonate
Enclosure Rating NEMA 4X (IP65)
Dimensions 9.5” x 8” x 4” (241 mm x 203 mm x 102 mm)
Display 320 x 240 pixel monochrome backlit display with touchscreen
Operating Ambient Temp -4 to 131 °F (-20 to 55 °C)
Storage Temperature -4 – 176°F (-20 – 80°C)
2.4 Variables and their Limits
Low Limit High Limit
Sensor input settings
Alarm limits Low end of sensor range High end of sensor range
Conductivity alarm dead band Low end of sensor range High end of sensor range
Cell constant 0.01 10
Installation Factor (Electrodeless conductivity only) 0.5 1.5
Cable length 0.1 3,000
PPM conversion factor (only if units = PPM) 0.001 10.000
Default temperature -5 500
Deadband Low end of sensor range High end of sensor range
4 mA value (analog input only) 0 100
20 mA value (analog input only) 0 100
Flow meter input settings
Totalizer alarm 0 100,000,000
Volume/contact 0 100,000
K Factor 0 1,000

6
Relay output settings
Output Limit Time 1 second 86,400 seconds (0 =
unlimited)
Hand Time Limit 1 second 86,400 seconds (0 =
unlimited)
Min Relay Cycle 0 seconds 300 seconds
Set Point Low end of sensor range High end of sensor range
Dead Band Low end of sensor range High end of sensor range
Feed duration (Flow Timer mode) 0 seconds 86,400 seconds
Accumulator volume (Flow Timer mode) 0 1,000,000
Feed Percentage (Bleed then Feed mode) 0% 100%
Feed Lockout Time Limit (Bleed & Feed, Bleed then
Feed modes) 0 seconds 86,400 seconds
Prebleed Conductivity (Biocide mode) 1 (0 = no prebleed) 30,000
Prebleed Time (Biocide mode) 0 seconds 86,400 seconds
Bleed Lockout(Biocide mode) 0 seconds 86,400 seconds
Event duration (Biocide, Timer modes) 0 seconds 86,400 seconds
Proportional band (Time or Pulse Proportional mode) 0 30,000
Sample period (Time Proportional mode) 10 seconds 3600 seconds
Sample Time (Intermittent Sampling mode) 0 seconds 3600 seconds
Hold Time (Intermittent Sampling mode) 0 seconds 3600 seconds
Maximum Blowdown (Intermittent Sampling mode) 0 seconds 3600 seconds
Wait Time (Intermittent Sampling mode) 0 seconds 86,400 seconds
Max Rate (Pulse Proportional mode) 10 pulses/minute 480 pulses/minute
Minimum Output (Pulse Proportional mode) 0% 100%
Maximum Output (Pulse Proportional mode) 0% 100%
Analog (4-20 mA) output settings
4 mA Value Low end of sensor range High end of sensor range
20 mA Value Low end of sensor range High end of sensor range
Hand Output 0% 100%
Set Point Low end of sensor range High end of sensor range
Proportional Band Low end of sensor range High end of sensor range
Minimum Output 0% 100%
Maximum Output 0% 100%
Off Mode Output 0% 100%
Error Output 0 mA 21 mA
Configuration settings
Local Password 0000 9999
VTouch update period 1 minute 1440 minutes
VTouch reply timeout 10 seconds 60 seconds
Graph settings
Low axis limit Low end of sensor range High end of sensor range
High axis limit Low end of sensor range High end of sensor range

7
3.0 UNPACKING & INSTALLATION
3.1 Unpacking the unit
Inspect the contents of the carton. Please notify the carrier immediately if there are any signs of
damage to the controller or its parts. Contact your distributor if any of the parts are missing. The
carton should contain a W600 series controller and an instruction manual. Any options or
accessories will be incorporated as ordered.
3.2 Mounting the electronic enclosure
The controller is supplied with mounting holes on the enclosure. It should be wall mounted with the
display at eye level, on a vibration-free surface, utilizing all four mounting holes for maximum
stability. Use M6 (1/4" diameter) fasteners that are appropriate for the substrate material of the wall.
The enclosure is NEMA 4X (IP65) rated. The maximum operating ambient temperature is 131°F
(55°C); this should be considered if installation is in a high temperature location. The enclosure
requires the following clearances:
Top: 2" (50 mm)
Left: 8" (203 mm) (not applicable for prewired models)
Right: 4" (102 mm)
Bottom: 7" (178 mm)
3.3 Sensor Installation
Refer to the specific instructions supplied with the sensor being used, for detailed installation
instructions.
General Guidelines
Locate the sensors where an active sample of water is available and where the sensors can easily be
removed for cleaning. Position the sensor such that air bubbles will not be trapped within the sensing
area. Position the sensor where sediment or oil will not accumulate within the sensing area.
In-Line Sensor Mounting
In-line mounted sensors must be situated so that the tee is always full and the sensors are never
subjected to a drop in water level resulting in dryness. Refer to Figure 2 for typical installation.
Tap off the discharge side of the recirculation pump to provide a minimum flow of 1 gallon per
minute through the flow switch manifold. The sample must flow into the bottom of the manifold in
order to close the flow switch, and return to a point of lower pressure in order to ensure flow. Install
an isolation valve on both sides of the manifold to stop flow for sensor maintenance.
IMPORTANT: To avoid cracking the female pipe threads on the supplied plumbing parts, use no
more than 3 wraps of Teflon tape and thread in the pipe FINGER tight plus 1/2 turn! Do not use
pipe dope to seal the threads of the flow switch because the clear plastic will crack!
Submersion Sensor Mounting
If the sensors are to be submersed in the process, mount them firmly to the tank, and protect the cable
with plastic pipe, sealed at the top with a cable gland, to prevent premature failure. Place the sensors
in an area of good solution movement.

8
Sensors should be located such that they respond rapidly to a well-mixed sample of the process water
and the treatment chemicals. If they are too close to the chemical injection point, they will see spikes
in concentration and cycle on and off too frequently. If they are too far away from the chemical
injection point, they will respond too slowly to the concentration changes, and you will overshoot the
set point.
The contacting conductivity sensor should be placed as close to the controller as possible, to a
maximum distance of 250 ft. (76 m). Less than 25 ft. (8 m) is recommended. The cable must be
shielded from background electrical noise. Always route low voltage (sensor) signals with at least a
6” (15 cm) separation from AC voltage wiring.
The electrodeless conductivity sensor should be placed as close to the controller as possible, to a
maximum distance of 250 ft. (76 m). Less than 25 ft. (8 m) is recommended. The cable must be
shielded from background electrical noise. Always route low voltage (sensor) signals with at least a
6” (15 cm) separation from AC voltage wiring. These sensors are affected by the geometry and
conductivity of their surroundings, so either maintain 6 inches (15 cm) of sample around the sensor
or ensure that any nearby conductive or non-conductive items are consistently positioned. Do not
install the sensor in the path of any electrical current that may be flowing in the solution, as this will
shift the conductivity reading.
The pH/ORP electrode should be placed as close to the controller as possible, to a maximum
distance of 1000 feet (300 m) from the controller. A junction box and shielded cable are available to
extend the standard 20 foot (6 m) length. pH and ORP electrodes must be installed such that the
measuring surfaces will always remain wet. A U-trap provided in the manifold design should achieve
this, even if the sample flow stops. These electrodes also must be installed with the measuring
surfaces pointing down; that is 5 degrees above the horizontal, at a minimum.
The disinfection sensor should be placed as close to the controller as possible, to a maximum
distance of 1000 feet (300 m) from the controller. A junction box and shielded cable are available to
extend the standard 20 foot (6 m) length. The sensor should be mounted such that the measuring
surfaces will always stay wet. If the membrane dries out, it will respond slowly to changing
disinfectant values for 24 hours, and if dried out repeatedly, will fail prematurely. The flow cell
should be placed on the discharge side of a circulation pump or downhill from a gravity feed. Flow
into the cell must come from the bottom side that has the ¾” x ¼” NPT reducing bushing installed.
The reducing bushing provides the flow velocity required for accurate readings and must not be
removed! A “U” trap should be installed so that if the flow stops, the sensor is still immersed in the
water. The outlet of the flow cell must be plumbed to open atmosphere unless the system pressure is
at or below 1 atmosphere. If the flow through the line cannot be stopped to allow for cleaning and
calibration of the sensor, then it should be placed in a by-pass line with isolation valves to allow for
sensor removal. Install the sensor vertically, with the measuring surface pointing down, at least 5
degrees above horizontal. Flow rate regulation must be done upstream from the sensor, because any
flow restriction downstream can increase the pressure above atmospheric and damage the membrane
cap!
Important Boiler Sensor Installation Notes: (refer to typical installation drawing)
1. Make sure the minimum water level in the boiler is at least 4-6 inches above the skimmer
blowdown line. If the skimmer line is closer to the surface, it is likely that steam will be drawn
into the line instead of boiler water. The skimmer line must also be installed above the highest
tube.
2. Maintain a 3/4 inch minimum pipe ID with no flow restrictions from the tap for the boiler
skimmer blowdown line to the electrode. If the ID is reduced below 3/4 inch, then flashing will

9
occur beyond that point and the conductivity reading will be low and erratic. Minimize the
usage of tees, valves, elbows or unions between the boiler and the electrode.
3. A manual shut off valve should be installed so that the electrode can be removed and
cleaned. This valve must be a full port valve in order to avoid a flow restriction.
4. Keep the distance between the tap for the boiler skimmer line to the electrode as short as
possible, to a maximum of 10 feet.
5. Mount the electrode in the side branch of a cross in a horizontal run of pipe. This will minimize
entrapment of steam around the electrode and will allow any solids to pass through.
6. There MUST be a flow restriction after the electrode and/or control valve in order to provide
back pressure. This flow restriction will be either a flow control valve or an orifice union. The
amount of the flow restriction will affect the blowdown rate as well, and should be sized
accordingly.
7. Install the motorized ball valve or solenoid valve per the manufacturer’s instructions.
8. For best results, align the hole in the conductivity electrode such that the direction of water flow
is through the hole.
Guide to Sizing Blowdown Valves and Orifice Plates
1. Determine the Rate of Steam Production in Pounds per Hour:
Either read off the boiler name plate (water-tube boilers) or
Calculate from horsepower rating (fire-tube boilers): HP x 34.5 = lbs/hr.
Example: 100 HP = 3450 lbs/hr.
2. Determine the Concentration Ratio (BASED ON FEEDWATER)
A water treatment chemical specialist should determine the desired number of cycles of
concentration. This is the ratio of TDS in the boiler water to TDS in the feedwater. Note that
feedwater means the water that is fed to the boiler from the deaerator and includes makeup water
plus condensate return. Example: 10 cycles of concentration has been recommended
3. Determine the Required Blowdown Rate in Pounds Per Hour
Blowdown Rate = Steam Production / (Concentration Ratio –1)
Example: 3450/(10-1) = 383.33 lbs./hr
4. Determine if Continuous or Intermittent Sampling is Required
Use intermittent sampling when the boiler operation or loading is intermittent, or on boilers where
the required blowdown rate is less than 25% of the smallest available flow control valve or less
than the flow through the smallest orifice. See the graphs on the next page.
Use continuous sampling when the boiler is operating 24 hours per day and the required
blowdown rate is more than 25% of the smallest applicable flow control valve or orifice. See the
graphs on the next page.
Use of a flow control valve will give you the best control of the process, since the flow rate can be
easily adjusted. The dial on the valve also gives you a visual indication if the flow rate has been
changed. If the valve clogs, it can be opened to clear the obstruction, and closed to the previous
position.

10
If an orifice plate is used, you must install a valve downstream from the orifice in order to fine
tune the flow rate and provide additional back pressure in many applications.
Example: An 80 psi boiler has a Required Blowdown Rate of 383.33 lbs./hr. The maximum flow
rate of the smallest flow control valve is 3250 lbs./hr. 3250 x 0.25 = 812.5 which is too high for
continuous sampling. Using an orifice, the flow rate through the smallest diameter plate is 1275
lbs./hr. This is too high for continuous sampling.
5. Determine the Orifice or Flow Control Valve Size for this Blowdown Rate
Use the following graphs to select a flow control device:

11
3.4 Icon Definitions
Symbol Publication Description
IEC 417, No.5019 Protective Conductor Terminal
IEC 417, No. 5007 On (Supply)
O IEC 417, No. 5008 Off (Supply)
ISO 3864, No. B.3.6 Caution, risk of electric shock
ISO 3864, No. B.3.1 Caution
3.5 Electrical installation
The various standard wiring options are shown in figure 1, below. Your controller will arrive from
the factory prewired or ready for hardwiring. Depending on your configuration of controller options,
you may be required to hardwire some or all of the input/output devices. Refer to figures 6 through
17 for circuit board layout and wiring.
Note: when wiring the optional flow meter contactor input, the 4-20 mA outputs or a remote flow
switch, it is advisable to use stranded, twisted, shielded pair wire between 22-26 AWG. Shield
should be terminated at the controller at the most convenient shield terminal.
CAUTION
1. There are live circuits inside the controller even when the power switch on the front panel
is in the OFF position! The front panel must never be opened before power to the controller
is REMOVED!
If your controller is prewired, it is supplied with an 8 foot, 18 AWG power cord with USA
style plug. A tool (#1 Phillips driver) is required to open the front panel.
2. When mounting the controller, make sure there is clear access to the disconnecting device!
3. The electrical installation of the controller must be done by trained personnel only and
conform to all applicable National, State and Local codes!
4. Proper grounding of this product is required. Any attempt to bypass the grounding will
compromise the safety of persons and property.
5. Operating this product in a manner not specified by Walchem may impair the protection
provided by the equipment.

12
Figure 1 Conduit Wiring

13
Figure 2 Typical Installation – Cooling Tower
HEAT
EXCHANGER
COO
LIN
G
T
O
WER
METERING
PUMPS
FLOW FLOW
SWITCH
SAMPLE
VALVE
1/4" POLYPRO
PANEL 19.5" x 11.75"
¾“ NPTF
¾“ NPTF
FLOW
CONDUCTIVITY
ELECTRODE
WEL pH/ORP
ELECTRODE
19.5"
11.75"

14
Figure 3 Typical Installation – Cooling Tower Submersion
ACID
BASE
SUBMERSION
ELECTRODE
pH
PROBE
AC POWE
R
FLOW OUTFLOW IN
1
2
3
4
5
6

15
Figure 4 Typical Installation – Boiler
RE
CO
MMENDED IN
S
TALLATI
O
N
INTERMITTENT SAMPLING
Install accessories
either vertically or
horizontally, per
manufacturer's
instructions.
To Drain
Skimmer Blowdown Line
3/4" Min. up to Electrode
Full Port Block
Valve
Manual Blowdown
(Normally Closed)
Motorized
Ball
or Solenoid
Valve
Flow
Control
Valve or
Orifice Union
CONDUCTIVITY
ELECTRODE
¾" TEE
2 ft.
minimum 1 to 3 ft. maximum
10 ft. max.
with minimal valves, elbows & unions
To Drain
Skimmer Blowdown Line
3/4" Min. up to Electrode
Full Port Block
Valve
Manual Blowdown
(Normally Closed)
Motorized
Ball
or
Solenoid
Valve
Flow
Control
Valve
or Orifice
Union
CONDUCTIVITY
ELECTRODE
¾" TEE
Flow
Control
Valve or
Orifice Union
RECOMMENDED INSTALLATION
CO
NTIN
UOUS
S
AMPLIN
G
TO
DRAIN
To Drain
To Drain

16
Figure 5 Typical Installation – Disinfection Sensor
ISOLATION
VALVE
(NORMALLY
OPEN)
RECIRCULATION
PUMP
1
2
3
4
5
6
ROTAMETER
30-100 LPH
PR
OC
E
SS
WATER
SAMPLE RETURN
1 ATMOSPHERE MAXIMUM
FLOW
SWITCH
SENSOR
FLOW CELL
FLOW
CONTROL
VALVE
SAMPLE
VALVE

17
Figure 6 Parts Identification
MAIN CONTROLLER BOARD RIBBON CABLE POWER SUPPLY EARTH GROUND
TERMINAL BLOCK FUSE
RELAY OUTPUT TERMINAL BLOCK
NEUTRAL TERMINAL BLOCK
AC POWER TERMINAL BLOCK
SENSOR, DIGITAL INPUT AND ANALOG OUTPUT TERMINAL BL
O
C
K
S
POWER RELAY BOARD
I/O SLOT 2 OPTION BOARD
I/O SLOT 1 BOARD
USB PORT
DUAL
ANALOG
OUTPUT
OPTION
ETHERNET
OPTION