EUTECH INSTRUMENTS DO 700 User manual

Instruction Manual
DO 700 Dissolved Oxygen/ºC/ºF
Bench Meter
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Part of Thermo Fisher Scientific 68X541703 Rev. 2. Sep 2010

TABLE OF CONTENTS
1. INTRODUCTION.............................................................. 1
2. GETTING STARTED........................................................ 2
2.1 Keypad Functions ...................................................................2
2.2 LCD Annunciators...................................................................3
2.3 Meter Connections..................................................................3
3. DISSOLVED OXYGEN / ATC ELECTRODE................... 4
4. CALIBRATION................................................................. 5
4.1 Temperature Calibration .........................................................6
4.2 % Saturation Calibration .........................................................7
4.3 100% Calibration.....................................................................7
4.4 0% Calibration.........................................................................7
4.5 mg/L or ppm (Concentration) Calibration................................8
5. SETUP FUNCTIONS........................................................ 9
5.1 1.0 CAL (Calibration)...............................................................9
5.2 2.0 ELE (Electrode Information)..............................................10
5.3 3.0 ConF (Configuration).........................................................10
5.4 3.1 rdY (Ready Stability Indicator / Auto Hold)........................10
5.5 3.2 ºC ºF (Celsius or Fahrenheit) ............................................10
5.6 3.3 dPr (Barometric Pressure Adjustment)..............................11
5.7 3.4 SALt (Salinity Adjustment) ................................................11
5.8 3.5 OFS (Offset Adjustment) from % mode.............................11
5.9 3.5 Unit (Unit Adjustment) from concentration mode...............12
5.10 4.0 rSt (Reset).........................................................................12
5.11 5.0 CLr (Clear Stored Memory)...............................................12
6. TAKING MEASUREMENTS ............................................ 13
6.1 HOLD Function .......................................................................14
6.2 Storing and Recalling Data .....................................................14
7. ELECTRODE MAINTENANCE........................................ 15
8. DISSOLVED OXYGEN THEORY .................................... 18

9. REPLACEMENTS AND ACCESSORIES........................ 22
10. TROUBLESHOOTING GUIDE......................................... 23
11. SPECIFICATIONS............................................................ 25
12. WARRANTY..................................................................... 26
13. RETURN OF ITEMS......................................................... 27

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1. INTRODUCTION
Thank you for purchasing our DO 700 series benchtop meter.
This microprocessor-based meter is economical and simple to
use. The design incorporates a large LCD for clear viewing, yet
offers a small footprint to conserve space.
The DO 700 measures Dissolved Oxygen in % saturation or
concentration (mg/L or ppm) with temperature (ºC or ºF).
Each meter includes a convenient slide-out card for quick
reference. Also included is an electrode arm and metal bracket
which can be easily attached to the left or right side of the meter
according to your preference.
We take great pride in every instrument we manufacture
and hope this one serves you well.

2. GETTING STARTED
2.1 Keypad Functions
Powers the meter on and off. Upon power on, the meter
automatically begins in the mode that was last used.
Calibration and memory values are retained even if meter
is unplugged.
Toggle between available measurement modes—%
saturation or concentration (mg/L or ppm). Also used to
switch to Temperature calibration during DO calibration
modes.
Press and hold for 5 seconds to enter SETUP mode.
Toggles between measurement and calibration modes.
In SETUP mode, returns user to the measurement mode.
Confirms calibration values in CAL mode.
Confirms selections in SETUP mode.
View recalled values in memory mode.
SIncrease value. Scroll up in SETUP & CAL modes.
MI (Memory Insert) stores values into memory.
MR (Memory Recall) recalls values from memory.
TDecrease value. Scroll down in SETUP & CAL modes.
Freezes measured reading. Press again to resume
live reading.
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2.2 LCD Annunciators
2.3 Meter Connections
DC Power supply
ATC Temperature connection of Dissolved Oxygen electrode
DO BNC connection of Dissolved Oxygen electrode
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3. DISSOLVED OXYGEN / ATC ELECTRODE
The DO 700 includes a galvanic DO
electrode with built in temperature
measurement.
The electrode has a dual cable; a BNC
connector for DO measurement and a mini-
phono plug for temperature. The electrode is
pre-filled with electrolyte that is separated
from the sample by an oxygen permeable
membrane. The membrane is pre-assembled
for you and fixed to a detachable cap. The
pre-assembled cap design allows simple
replacement and fast conditioning.
The electrode is light-weight with a 12-mm
body diameter and a 16-mm tip diameter
from at the detachable Noryl cap. The
compact sensing area reduces air
entrapment resulting in quick, accurate, and
stable readings.
Provide simple stirring for best results—
ideally achieve a minimum water flow rate of
2 inch/second on the membrane.
The probe is not recommended for samples
beyond 0 to 50 °C.
The membrane is thin and can be replaced if damaged. Use care to
protect from scratches, abrasion, or contact with solids. For best
results keep membrane clean by rinsing after daily use. See Section 7
– Electrode Maintenance.
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4. CALIBRATION
The DO 700 has three measurement modes; DO as % saturation, DO
as mg/L (or ppm) concentration, and temperature.
Dissolved oxygen levels vary with temperature, barometric pressure,
and salinity, so calibration must be performed with consideration of
these factors. It is necessary to set the proper temperature,
barometric pressure and salinity values prior to performing any
DO calibration or measurement.
See Section 4.1 — Temperature Calibration.
See Section 5.6 — Barometric Pressure Adjustment.
See Section 5.7 — Salinity Adjustment.
The DO 700 will accept two % saturation calibration points; 100%
using saturated air or air-saturated water, and 0% using zero oxygen
solution. When 100% or 0% calibration is performed, the concentration
value is adjusted accordingly. Therefore, it is not necessary to calibrate
the concentration mode. If calibrating for 0% oxygen, note that the
meter will take several minutes to reach 0% saturation value and
constant stirring is not required.
The following table lists calibration values in % saturation calibration
mode with two different barometric pressures. Note that the saturation
value (92.1%) has decreased due to the lower barometric pressure
entered.
% Saturation
(of factory default value) Calibration Value (760mmHg) Calibration Value (700mmHg)
less than 10% 0% 0%
10.1% to 49.9% CAL ERR CAL ERR
50% to 150% 100% 92.1%
If calibration is attempted from 10.1% to 49.9%, CAL Err message is
shown—calibration is rejected and the display will return to calibration
mode.

The DO 700 will accept one calibration point in concentration mode.
The minimum value is 2 mg/L (ppm), and the calibration window is +/-
40% of the factory default value.
Temperature and % saturation calibration should take place before
attempting to perform mg/L (ppm) concentration calibration.
Calibration of the concentration mode will only replace the previous
concentration calibration and does not affect the % saturation
calibration.
To offset your % saturation reading to match another instrument, see
Section 5.8 – Offset Adjustment.
Perform daily calibration for best results. New calibration values will
automatically override the existing data. To completely recalibrate the
meter and when installing a replacement electrode, it is best to clear all
calibration data. See Section 5.10 – Reset.
4.1 Temperature Calibration
For best DO accuracy, ensure that the temperature is accurate. The
thermistor sensor used for automatic temperature compensation and
measurement is accurate and stable, so frequent calibration isn’t
required. Temperature calibration is recommended upon probe
replacement, whenever the temperature reading is suspect, or if
matching against a certified thermometer is desired.
The DO 700 will default to 25 ºC / 77 ºF when the ATC plug is not
connected.
1) Place the probe into a solution with a known accurate temperature
such as a constant temperature bath.
2) Press followed by . The primary display shows the
measured temperature while the secondary display shows the
factory default temperature.
4) Adjust the temperature using or . Press to accept or
to cancel. The meter allows an adjustable maximum value of ±
5ºC (or ± 9ºF) from the factory default temperature.
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