||PINPOINT® ORP Controller
II. General Specifications
III. Displays & Adjustments
IV. Important Note on Probe Placement
V. Adjusting the Controller Setpoints
VI. Connecting Controlled Devices
This device consists of an ORP Monitor and electronics, which control external devices, based on the ORP reading.
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 ozone gas into their system with this
instrument and there can be undesirable results if ozone is added to the
system in an uncontrolled fashion. It is critical that one pay special
attention to the placement of the ORP probe in the system. You must
frequently check the calibration and age of the ORP probe. 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 ORP and ozone gas may be added in a completely
uncontrolled fashion. Installing an ORP Controller on your system does
not mean that you no longer have to pay attention to it. You must still
monitor the aquarium so that you can note when a problem exists and
correct it in a timely fashion.
II. GENERAL SPECIFICATIONS
ORP Measurement Range –1,999 to +1,999 mV
ORP Setpoint Range 0 to 1,000 mV
3 1/2 Digit LCD Display
Resolution 1 mV Unit
2 Independent 5 Amp (110 VAC) Relay Outputs
III. Displays and Adjustments
ORP Monitor Adjustment & Instrument Status
Controller Set Point Block
Controller Status LEDs
110 VAC Outlets (#1 &2)
Platinum Band ORP Probe
UPPER LEFT (ORP Display)
The 3 1/2 digit LCD (Fig. A) at the top left of the
controller displays a numeric value corresponding either to the ORP, or
the controller setpoints.
LOWER LEFT (ORP monitor Adjustment & Instrument Status)
The red POWER LED (Fig. B) is illuminated when the power
is turned on to the controller. The ORP LED (Fig. C) is illuminated when
the display is indicating the ORP as measured through the probe. The
ORP LED is off when the display is indicating either the high or low
CENTER (Controller Setpoint Block)
There are two potentiometers that are used to adjust the
controller setpoints. They control the RANGE (Fig. D) and CENTER VALUE
(Fig. E) of the controller, respectively. Detailed information regarding
their adjustment is given later in the ADJUSTING THE CONTROLLER
LOWER RIGHT (Display Mode)
The position of the SLIDE SWITCH (Fig. F) will determine
what the LED display will show. At the center position, the display
indicates the ORP that the probe is measuring, and the red ORP LED (Fig.
C) 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 LEDs)
There are a total of 4 LEDs here. The upper row (Fig. G)
shows the status of the 110 VAC outlets, which you will find on the back
of the controller beneath the LCD ORP display. The lower LED lights
(Fig. H) are activated when the slide switch is placed in the HIGH or
110 VAC OUTLETS
There are two outlets, which will be energized when the ORP is
above (outlet #1) or below (outlet #2) the controller setpoints. A
common application for the controller will be to control the addition of
ozone gas to the system. Since the addition of ozone gas raises the
ORP, an ozonizer would be plugged into the LOW control outlet (Outlet
An ORP electrode is supplied with the controller. As
shipped, a plastic bottle will protect the end of the electrode. Gently
remove the bottle. There is a small amount of fluid on the sponge fiber
inside the bottle. It is a mixture of #4.0 calibration fluid + 3M KCL
which 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.
ORP Calibration (Lower Left)
For the highest precision you should calibrate the ORP
probe immediately and every month thereafter to insure readings. Attach
the probe BNC connector to the controller and place the selector switch
to the middle (read) position. Insert the ORP probe tip into the pouch
containing the ORP 400mV calibration fluid. Turn the CALIB adjustment
screw (Fig. I) with the supplied screwdriver to tune the probe to 400
mV. Discard the calibration after use. Wash off the probe with fresh
water before placing into the aquarium.
IV. PROPER PLACEMENT OF THE ORP 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 lower pink band of the
electrode, the ORP probe will not read properly. If the erroneously
measured ORP is higher than the controller setpoint, devices connected
to that outlet will remain permanently ON, irrespective of the actual
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."
V. ADJUSTING THE CONTROLLER SETPOINTS
The PINPOINT® ORP Controller is capable of controlling ORP
within the range of pH 0 through 1,000 mV. After the selection of the
ORP setpoint, you will find that the controller can create a span around
this setpoint, both above and below, from about +/- 10 mV units to +/-
100 mV units.
Two adjustment screws in the setpoint block will determine the
controller ORP setpoints. The right adjustment screw determines the
"center value" or the point halfway between the high and low setpoints.
Note that the Center Value is NOT directly displayed and must be
calculated. The left adjustment screw controls the range both above and
below the selected ORP setpoint.
As an illustration of how the two adjustments are related, consider the following:
When the measured ORP falls to a value below the LOW setpoint,
the device attached to the LOW outlet is activated and will remain ON
until the ORP is brought to the center value at which time it will be
Adjusting the Controller Setpoints
the "Center Value" that you wish to establish and the range around this
center value you feel is acceptable (between 10 and 100 mV units).
Remember, if you are only adding ozone gas, you will have ORP control in
only one direction from a LOW value to the Center Value.
- Turn the range adjustment screw to its minimum setting.
the display mode slides switch (HIGH/READ/LOW; on the right side of the
controller) between the high and low setpoints to show the ORP range
presently selected. Slide the switch to the LOW position.
turning the CENTER VALUE adjustment screw with a fine blade
screwdriver, adjust the lower limit to about 10 mV below the center
value you have determined is best for your application.
display the high and low ORP controller settings and take the average
by adding the high and low setting together then dividing by 2. The
result is the Center Value.
adjust the range adjustment screw to give the desired ORP range, Again,
use the display mode switch to show the high and low values. When they
are acceptable to you, return the display mode switch to the READ
position, and verify that the red ORP LED at the lower left corner of
the instrument is ON. You have now established the controller setpoints.
VI.CONNECTING CONTROLLED DEVICES
The PINPOINT® ORP Controller is capable of driving devices to control both the high and low ORP limits of the system.
When the measured ORP is greater than that of the high ORP limit
you have established, Outlet 1 will be energized which will activate a
device to lower the ORP (if you so desire). When the measured ORP is
lower than the low ORP limit, Outlet 2 will be energized which will
activate a device to raise the ORP. There are also LEDs on the front of
the controller which are illuminated when the respective outlets are
You should make every effort to insure that the pumps, ozonizers
or valves you attach are of good quality and checked frequently.
Copyright / Warranty
PINPOINT® ORP 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
Any defective product to be returned 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 914 763 5367