American Marine Pinpoint pH Controller User manual

AmericanMarineInc.
54DanburyRoad Suite172
Ridgefield,CT06877 U.S.A.
Phone/FAX[phone]
www.americanmarineusa.com
PINPOINT ®
pHController
UsersManual
AmericanMarineInc.
54DanburyRoad Suite172
Ridgefield,CT06877 U.S.A.
FAX/Phone[phone]
www.americanmarineusa.com

PINPOINT pH Controller USERS Manual
I. Overview
II. General Specifications
III. Displays & Adjustments
IV. pH Calibration
V. Important Note on Probe Placement
VI. Adjusting the Controller Setpoints
VII. pH Monitor Theory
I. Overview
This device consists of a pH Monitor and electronics, which control external
devices, based on the pH reading. Accordingly, there are two adjustments that
must be made to the controller before putting into service. The calibration of the
electronics which read the pH and the adjustments of the controller setpoints.
After the controller is in service, it will be necessary to re-confirm and perhaps re-
calibrate the pH monitor.
It is important that you understand these instructions and it is critical that you
follow the cautions in this manual. Most users will be controlling the addition of
CO2 into their system with this instrument and there can be disastrous results if
CO2, another acid or a base is added to the system in an uncontrolled fashion. It is
critical that one pay special attention to the placement of the pH probe in the
system. You must frequently check the condition and calibration of the pH probe.
We strongly require that you build sanity into your system. Needle valves, and
similar devices, should be designed to throttle-down the flow of gases into the
system at a reasonable rate. If a base is being added, the maximum rate of addition
should be slow enough so that there are not disastrous consequences over a short
period of time. Control electronics are not human, they are not intelligent and they
can not “know” when something has happened to make their input or output
invalid. If the probe is not immersed in the system, it will no longer be reading the
correct pH; either acid or base might be added in a completely uncontrolled
fashion. If solenoid valve sticks open, the controller will not be able to shut it off.
So you must be very certain that the pH probe will not become uncovered and your
needle valve settings should be chosen so that if the control solenoid valve sticks
open, you will have some reasonable period of time to notice that there is a
problem. Installing a pH Controller on your system does not mean that you no
longer have to pay attention to it. You must still monitor the system so that you
can note when a problem exists and correct it in a timely fashion.
II. GENERAL SPECIFICATIONS
pH Measurement Range 1.00 - 14.00
pH Setpoint Range 4.00 - 10.00
3 1/2 Digit LCD Display
Resolution 00.00 pH Unit
2 Independent 5 Amp 110 VAC Relay Outputs
III. Displays and Adjustments
pH Display
pH Monitor Adjustment & Instrument Status
Controller Set Point Block
Display Mode
Controller Status LED’s
110 VAC Outlets (#1 &2)
pH Probe
UPPER LEFT (pH Display)
The 3 1/2 digit LCD (Fig. A) at the top left of the controller displays a
numeric value corresponding either to the pH as measured through the probe, or
the high or low controller setpoints.
LOWER LEFT (pH monitor Adjustment & Instrument Status)
Below the display are two adjustment screws, which are used to calibrate
the electronics to properly read the pH, and two LED’s which report the status of
the instrument.
The adjustment screw marked “CALIB” (Fig. B) is used to zero the pH
monitoring electronics, and the “SLOPE” (Fig. C) is used to adjust the slope.
Detailed information on how to make these adjustments is given later.
The red POWER LED (Fig. D) is illuminated when the power is turned on to
the controller. The pH LED (Fig. E) is illuminated when the display is indicating the

pH as measured through the probe with the slide switch in the “read” position. The
pH LED is off when the display is indicating either the high or low controller
setpoints.
CENTER (Controller Setpoint Block)
There are two potentiometers that are used to adjust the controller
setpoints. They control the RANGE (Fig. F) and CENTER VALUE (Fig. G) of the
controller, respectively. Detailed information regarding their adjustment is given
later in the ADJUSTING THE CONTROLLER section.
LOWER RIGHT (Display Mode)
The position of the SLIDE SWITCH (Fig. H) determines what the LED
display will show. At the center position, the display indicates the pH that the
probe is measuring, and the red pH LED (Fig. E) at the lower left of the instrument
will be illuminated. Sliding the switch up or down will cause the display to show
the high and low controller setpoints, respectively.
UPPER RIGHT (Controller Status LED’s)
There are a total of 4 LED’s here. The upper row (Fig. I) shows the status
of the 110 VAC outlets, which you will find, on the back of the controller beneath
the LCD pH display. The lower LED lights (Fig. J) are activated when the slide
switch is in either the HIGH or LOW position.
110 VAC OUTLETS
There are two outlets, which will be energized when the pH is above
(outlet #1) or below (outlet #2) the controller setpoints. A common application for
the controller will be to control the addition of CO2 to the system. Since the
addition of carbon dioxide lowers the pH, a NORMALLY CLOSED solenoid valve
controlling the flow of CO2 would be plugged into the HIGH control outlet (Outlet
#1). If a basic substance is being dispensed into the system (i.e. a lime water
reactor for a reef aquarium) the device(s) controlling the flow would be attached to
the LOW control outlet # 2.
NORMALLY CLOSED means that the valve will be closed when NOT energized.
A pH electrode is supplied with the controller. A plastic fluid-filled cap
will protect the end of the electrode. The fluid inside the cap is a mixture of #4.0
calibration fluid + 3M KCL. This is commonly known as storage fluid. There is a
suction cup attached to the electrode, which may be used to secure it, or a user-
devised scheme of holding the electrode may be employed.
IV CALIBRATING THE pH METER SUBSYSTEM
This is a two-point calibration instrument therefore TWO different
calibrations must always be used. A pH 7.00 fluid must be used to set the CALIB
and a pH 10.00 or 4.00 fluid is used to set the slope.
COMPLETE INSTRUCTIONS:
Before you begin the calibration, you should disconnect the pumps or
valves that you are controlling, because the pH electrode will be put into solutions
with a pH that is probably far outside the controller limits you have established.
Before you begin, make sure that you have the pH calibration fluids, and
some room temperature tap water to rinse the electrode between calibration
solutions. You must have a #7.00 calibration solution, and another solution with
either be higher or lower pH (typically 4 or 10). If you are doing this for the first
time, read through these instructions once to determine what is required before
you begin.
1.Set the display mode switch (far right) to the central position (read). The
pH LED (lower left) should be illuminated.
2.Remove the plastic cap protecting the end of the electrode if you are
doing this for the first time. If the electrode has already been in service you should
note the condition of the electrode and clean it if required.
3.Rinse the electrode with room temperature tap water taking cares to
remove any accumulated salt. Rinsing the electrode prevents you from carrying
over contaminating substances into the calibration solutions. Gently shake the
electrode to remove any clinging drops of water.
4.Immerse the tip (bottom 1 inch) of the electrode into the pH 7 calibration
fluid. It is important to use the pH 7 solution first. Be sure that the tip of the probe
is fully immersed in the calibration fluid for a stable and reliable result.
5. Keeping the glass bulb immersed, gently swirl the ends if the electrode
in the calibration fluid until the pH reading stabilizes. If the electrode is in good
condition, the reading should stabilize in a few seconds. If the electrode does not

easily stabilize; this may be a sign that the electrode is in need of cleaning or
should soon be replaced.
6.Adjust the CALIB screw to bring the displayed pH to about 7.00
7.Remove the electrode from the pH 7.0 calibration solution and rinse it
with room temperature tap water. Gently shake the electrode to remove clinging
drops of water.
8.Immerse the end of the electrode into either the low or high calibration
fluid. Usually pH 4 or pH 10 is the most common. Swirl the end of the electrode in
the fluid until you obtain a stable reading, then adjust the SLOPE screw until the
display shows the value of your calibration fluid (typically 4.00 or 10.00).
9. Again, rinse the electrode with room temperature tap water and shake
of any clinging drops.
10.Re-immerse the electrode in the pH 7 calibration solution and now
repeat steps 6-7-8 until the display shows 7.00 in the pH 7 fluid and 4.00 or 10.00
in the other calibration fluid that you have selected.
11.Rinse the electrode and return it to service in your system. Remember
that the sensitive glass bulb of the electrode must not be allowed to dry out. Use
the clear plastic cap filled with storage fluid or pH 4 calibration fluid when not in
use.
The pH calibration process is now complete.
V. PROPER PLACEMENT OF THE pH ELECTRODE
When the controller is operational, it is critical that the tip (bottom 1-inch)
of the electrode be immersed in the system at all times. If the water level falls
below the sensing tip of the electrode, the pH probe will not read properly. If the
erroneously measured pH is higher than the controller setpoint, devices connected
to that outlet will remain permanently ON, irrespective of the actual pH.
Take some time to determine how much the fluid level around the probe
will fluctuate. Adjust the position of the probe accordingly.
Consider the final placement of the probe and attach it securely so that it
remains in position. Be sure to check the probe position occasionally. Complacency
usually sets in when you feel that “Everything is running fine”.
VI. ADJUSTING THE CONTROLLER SETPOINTS
The PINPOINT pH Controller is capable of controlling pH within the range
of pH 4 through pH 10. After the selection of the pH setpoint you will find that the
controller can create a span around this setpoint, both above and below, from
about +/- 0.1 pH unit to +/- 1.0 pH unit.
Two adjustment screws on the front panel determine the controller pH
setpoints. The right adjustment screw determines the “center value” or the point
halfway between the high and low setpoints. The left adjustment screw controls
the range both above and below the selected pH setpoint.
As an illustration of how the two adjustments are related, consider the
following:
When the measured pH moves from the center of the acceptable pH range to above
the high setpoint, the device attached to the HI outlet is activated and will remain
ON until the pH is brought to the center value.
Adjusting the Controller Setpoints
Determine the “Center Value” that you wish to establish and the range around this
center value you feel is acceptable (between +/- 0.1 and 1.0 pH units). Remember,
if you are only adding CO2, you will have pH control in only one direction.
For example, if the acceptable range is a total of .4 pH units from a LOW of 6.8 to a
HIGH of 7.2 this means that the center value is 7.0 since it is equidistant from 7.2
and 6.8 When the pH rises to 7.2 the CO2 will be activated (Outlet #1) until the pH
reaches 7.0(Center Value) at which time it will be turned off.
If you would like to use a different center value, 8.0 for example, then adjust the
center value screw until the HIGH setpoint is 8.2 This will make the LOW setpoint
7.8 If you would like the range to be a total of .2 pH units then adjust the range
screw accordingly. If you would like to have a larger range of .8 pH units then
adjust the range screw accordingly.
Remember to slide the switch between the HIGH and LOW positions to determine
the center value as well as the range that you have selected. Keep in mind that the
Center Value is not displayed and must be calculated as the average of the HIGH
and the LOW setting.

VII. pH Monitor Theory
To make the above adjustment of the pH meter portion of the controller more
comprehensible, this is a brief discussion of how pH electrodes work.
There is a special glass bulb that is in contact with the solution. There are
also special solutions inside the body of the electrode, and a liquid junction that
allows minute amounts of ions to exchange between the electrode body and the
solution. This junction completes the electrical circuit. The pH Electrode acts like
an extremely weak battery, whose voltage is dependent upon the amount of H+
ions present in solution. Because the electrical properties of this special glass are
dependent on the H+ ion concentration of the solution in contact with the glass
bulb. Because this current is very small, the signal must be handled very carefully,
and the electronics in this monitor have been specially designed to handle very
weak voltage, measure it accurately, translate it from a voltage to pH units,
display that quantity and pass it to the controller subsystem.
The voltage output from this very weak battery happens to be 0 mV at pH
7. This is why a pH 7 solution is always used to “zero” the meter. The zero
happens to be marked CALIB on the instrument case. A second standard solution,
with either a pH higher or lower than 7 (usually 4 or 10) is used to adjust the slope
for the response of the electronics. Since the pH scale is linear in nature you may
be interested to know that this instrument will adjust 59mV per pH unit step.

Copyright / Warranty
PINPOINT pH Controller by American Marine inc. is warranted to be free
of defects in Material and workmanship for a period of 2 years from date of sale.
Positive proof of purchase is required for warranty claim.
American Marine Inc. will not be liable for any costs of removal,
installation, transportation charges, or any other charges, which may result in
connection with a warranty claim.
American Marine Inc. will not be liable for any damage or wear to
products or livestock caused by abnormal operating conditions, water damage,
abuse, misuse, unauthorized alteration or repair or if the product was not installed
in accordance with the printed operating instructions.
Any defective product must be sent freight prepaid with appropriate
documentation supporting the warranty claim. Replacement or repair will be at the
discretion of American Marine Inc. Typical turnaround time within 48 hours.
Overnight delivery available.
American Marine Inc.
54 Danbury Road Suite 172
Ridgefield, CT 06877 USA
FAX/Phone [phone]
www.americanmarineusa.com
PINPOINT pH Controller
***This example is for a CO2 dosing system.
When CO2 is added to water; it will lower the pH
of the water.
-You must first select an acceptable range of pH
like 6.6 to 6.4
At any pH value over 6.6 Outlet #1 will be
energized and the CO2 will bubble into the water
until the pH reaches the level of 6.4 At the 6.4
level the CO2 will shut off and stay off until the pH
rises above the 6.6 level.
-To achieve these setpoints, the selector switch
should read 6.60 when placed in the HI position
and 6.20 when put in the LO position. The Center
Value is the number that is exactly between the HI
and the LO. The Center Value in this example is
6.40 This Center Value must be calculated; it is not
displayed.
-To arrange these settings (HI=6.60, LO=6.20,
Center Value=6.40) into the controller you must do
the following 2 part adjustments.
1-Put the selector switch to the HI position and
note the number. Then put the switch to the LO

position and note the number. By adjusting the
RANGE screw in the center of the controller you
must create a difference of 0.40 between the HI
and the LO. It is NOT important at all which
numbers are used, it is important that there the
difference of 0.40 between HI to LO. The numbers
may be HI-6.40 and LO-6.00 or perhaps HI-8.98
and LO-8.58. The only thing is that the difference
from HI to LO is 0.40 pH units.
2-With the selector switch in the HI position, adjust
the Center Value screw until it reads 6.60
That is all!
What you have done is to put the HI setting to 6.60
and the LO setting is 6.20 therefore the Center
value is 6.40
PINPOINT pH Controller
Has control ability in both
directions
In our example the setpoints are as follows:
HI 6.60
Center Value 6.40
LO 6.20
The controller is set up to control CO2. There is a
solenoid attached to Outlet #1 in the back of the
controller.
When the pH of the water is above 6.60 the Outlet
#1 will energize the solenoid and CO2 will bubble
into the water until the pH of the water reaches the
Center Value of 6.40. When the pH value reaches
the Center Value of 6.40 the CO2 will shut off.
After the CO2 is shut down if the water still has a
falling pH then the LO setting is important. If the pH
of the water is below the LO setting of 6.20 then

outlet #2 will energize. Outlet #2 should have a
regular air pump connected to it and the air should
disperse in the water by an airstone. The air will
drive off the extra CO2 and return the water to the
Center value pH of 6.40 at that time the air pump
will shut off.
***The American Marine line of pH and ORP
Controllers are unique because they can give
control at both directions around the center value.
The user can determine the range of acceptable pH
around the center value.
Calcium Reactor Theory and Setup
•Calcium Reactors are excellent systems designed
to add a steady amount of natural elemental
calcium and minerals to a marine aquarium system.
This is achieved by the careful addition of
CO2 gas to the system seawater, thus lowering its
pH to the acidic range and passing this seawater
through aragonite coral chips housed inside the
reactor <see diagram>.
Because the CO2 treated seawater has a pH
in the range of 6.6-6.8 (or lower); it will readily
dissolve aragonite coral chips housed inside the
calcium reactor. This enriched calcium seawater,
also called effluent, should be sufficiently aerated
to drive off the CO2 and return the pH to the
normal range while still carrying the additional
calcium in solution before it is re-introduced back
into the aquarium.
You will be controlling the pH of the fluid
inside the reactor. Generally speaking a pH of 6.6-
6.8 (or lower) will readily dissolve aragonite media.
If the pH of the seawater surrounding the aragonite
is too low, the aragonite will turn to “mush” and no
longer have fluid flow through the chips. If the pH
is too high there will not be a sufficient acid
environment to dissolve the aragonite. Trial and
error with your brand of aragonite should be
performed.
***Note: Properly designed Calcium Reactor
Systems will add natural elemental calcium and
minerals to your system and will have virtually no
effect on the pH of the aquarium.
There are several equipment considerations:
•Calcium Reactor
•Aragonite Media
•CO2 Tank
•Electric CO2 Solenoid
•PINPOINT pH Controller

Consider the following setup into a marine aquarium
sump:

•Calcium Reactor-houses the aragonite chips and
has a mechanism to infuse CO2 gas inside the
reactor. Some models have a built-in port to
accommodate a pH probe. Many reactors do not
have a port. Models without a port should have
the output water (effluent) exit the reactor and
collect in a small cup located in the sump area
The probe of the pH Controller should be
installed in the collection cup so as to measure
the pH of the seawater from the Calcium
Reactor. As this collection cup fills, it will
overflow into sump where it should be properly
aerated to drive off the CO2 and return the pH
back to normal seawater levels before it enters
the aquarium. An airstone or aerating powerhead
in the sump area can be beneficial.
•CO2 Tank or Bottle-This will be your source of
CO2 gas. Obviously CO2 gas when mixed with
seawater will lower the pH of seawater. CO2
bottles are easily, and inexpensively, refilled at
any welding supply store or any outlet that will
recharge fire extinguishers.
•Electric CO2 Solenoid-An electrically activated
valve that when energized by the outlet on the
back of the PINPOINT pH Controller, will allow
CO2 gas to exit the CO2 bottle to be released in
the aragonite of the Calcium Reactor. This CO2
gas will quickly lower the pH of the seawater
inside the reactor. A bubble counter, if available,
will visually indicate the volume of CO2 exiting
the bottle. This gas volume can be adjusted via
the needle valve on the solenoid.
•Aragonite-Basically coral fragment. You should
experiment to find the pH levels that will dissolve
the aragonite most efficiently. If the pH is too
low the aragonite will turn to “mush” and no
longer have flow through it. If the pH is too high
then the aragonite will not be dissolved
sufficiently.
•PINPOINT pH Controller-The electronic pH
measurement and control device that will
activate the CO2 solenoid to start or stop the
CO2 gas flow to the reactor.
Not all pH Controllers can control devices that
will influence pH in both an increasing and a
decreasing pH direction as needed. The
PINPOINT pH Controller is perfectly suited for
any calcium reactor application by controlling pH
downward during CO2 addition. It will also
control pH upward by using a regular air pump to
drive off the CO2 from seawater.

Typical setpoints would be to begin the CO2
flow at a pH of 6.8 and stop the CO2 flow when
the pH of 6.6 is reached.
The PINPOINT pH Controller:
-will automate the proper pH settings inside the
calcium reactor
-save CO2 by using it only when necessary
-save aragonite by keeping the pH levels in the
proper range
-allow easier adjustment of flow through the
reactor by keeping pH in the proper range
through a range of different fluid flow and CO2
volumes
•Aragonite-Basically coral fragment. You should
find the pH levels that will dissolve the aragonite
most efficiently. If the pH is too low the
aragonite will turn to “mush” and no longer have
flow through it. If the pH is too high then the
aragonite will not be dissolved sufficiently.
To optimize reactor efficiency experiment with:
-lower pH settings to dissolve more aragonite
-Increased CO2 flow to the reactor
-decrease (or increase) the water flow through the
reactor
-install an aerating powerhead in the sump to drive
out the CO2 gas and return the effluent to normal
seawater pH levels before returning to the
aquarium.
Discussion:
Some hobbyist want to place the pH electrode
directly into the aquarium water. Their objective is
to use the pH controller as a safety device to shut
off the CO2 gas in the event the aquarium pH
becomes too low because the effluent containing
the CO2 is being introduced back to the aquarium
water at too fast a rate and/or without proper
aeration.
Pros:
-You can use the PINPOINT pH Controller to
monitor the pH of your aquarium
Cons:
-CO2 gas will be infused constantly whether it is
actually needed or not
-You will not be able to monitor the pH of the
seawater inside the reactor.
-Flow rate and CO2 input to the reactor will be
more difficult to adjust and therefore the reactor pH
will more easily be “out of optimal range”
frequently too high or too low.