LaMotte DA-DS-1939 User Manual

CONDUCTIVITY/TDS METER

OPERATOR’S MANUAL

MODEL DA-DS · CODE 1939

SPECIFICATIONS

METER

A. Range:

0 - 5,000 micromhos/cm
0 - 3,500 Total Dissolved Solids

B. Accuracy:

2% full scale reading

C. Precision:

0.5% full scale reading

FUNCTION CONTROLS

A. Operation Switch:

BATCK - check battery reserve
OFF - turn meter off
CAL - calibrate instrument
ON - read conductivity or Total Dissolved Solids (TDS)

B. Calibration:

Calibrates instrument by regulating voltage potential

C. Temperature Compensation:

0-100oC - adjusts instrument to temperature of sample
being tested

D. Other Specifications:

Power: Single 9V Transistor Battery
Physical Dimensions: 3-3/4" width x 2-5/8" depth x 6-1/4"

Weight: 1.4 lbs
Jack Receptacle: accepts 9V AC Adapter, 3.5mm plug

height

Code 1708 (optional)

PROBE:

Range: 0-5,000 micromhos/cm
Size: 6" x 1/2"
Weight: 2 oz
Elements: Carbon (non-fouling)
Probe Constant: 5.0/cm
Connector: BNC

NOTES ON THE USE OF CONDUCTIVITY PROBE

1. The sensing element of the conductivity probe consists of thin metal
plates, rigidly supported in a rugged plastic material. These metal plates
have a very precise parallel spacing which determines the probe cell
constant. To keep this spacing and to assure accurate results, it is
essential that the probe is properly maintained and kept clean.

2. When conductivity measurements are made, the probe must be
immersed in sufficient solution to cover the bottom groove. The probe
may be completely immersed within the sample without adversely
affecting the results.

3. There is a tendency for the conductivity probe to entrap air bubbles
which may result in erroneous readings. After the probe is immersed in
the test solution, tap or “jiggle” the probe to remove trapped air
bubbles.

4. The conductivity probe must be kept from contacting the bottom or
sides of the containers which hold the sample. Contact with surfaces
other than the solution might result in inaccurate readings since the
current flow may be altered between the probe elements.

5. After the completion of the conductivity measurement, rinse inside and
outside of probe thoroughly with water, preferably distilled water. Allow
probe to drain completely before storing. The probe may be stored dry
indefinitely without any damage.

DETERMINATION OF CONDUCTIVITY &
TOTAL DISSOLVED SALTS FOR WATER

1. With control knob in the “OFF” position, meter pointer must balance
at zero. To adjust the zero position, use meter-zero adjusting screw (“X”
slot screw on front of meter face usually located under LaMotte logo
sticker). The mirror-faced scale insures accurate readings by eliminating
errors due to parallax problems when the indicating needle and the
scale are not properly aligned by the reader’s eye.

2. Plug the probe into BNC receptacle located above and to the left of
meter movement.

3. Switch the control knob to the “BATCK” position. Meter should
indicate greater than 4,000 micromhos/cm. If not, replace battery. (See
instructions for battery replacement.)