PINPOINT® Salinity Monitor User's Guide

American Marine is proud to introduce PINPOINT® Salinity Monitor, the only truly accurate and affordable Salinity measurement system. A 9-volt battery should be used for intermittent or field use while a PINPOINT® AC Adapter Kit can also be installed. Battery replacement is visually indicated on the display as "LOBAT."

NOTE: The Salinity Monitor unit is NOT waterproof and must be operated on a dry surface. Liquid contact on the printed circuit board will cause corrosion and void warranty.

Set-up
Unwrap the protective plastic packaging from the Salinity Monitor Unit. Remove the battery cover on the back of the monitor and install a 9-volt battery or the PINPOINT® AC Adapter Kit. Activate the unit by setting the power switch to the ON position. Use the pop-up stand on back and place meter on any flat, dry surface. Velcro can be used to mount the meter onto a vertical surface.

Your PINPOINT® Salinity Monitor is now ready for calibration.

Calibration Procedure
Note: The meter should be calibrated immediately before use. The calibration should be checked occasionally to verify your readings. The precise measurement of Salt by electronic conductive means has long been considered to be the most accurate method, especially when compared to Specific Gravity / Density (hydrometers) and refractometers.

Marine environments should use the calibration fluid labeled 53.0mS. Empty the 53.0mS into a small, clean cup and swirl the probe in the fluid making sure that no air bubbles have accumulated under the probe. Wait 1–2 minutes to allow for the temperature thermistor inside the probe tip to properly compensate for any temperature differences between the fluid and the probe. Using a miniature screwdriver, turn screw #3 (see diagram) until the display matches the 53.0mS fluid (±0.5). The calibration adjustment screw #3 is located inside the battery compartment most toward the center of the meter. Note that the conversion chart will convert the display readings to either ppt (‰ Salt) and/or SG (Specific Gravity). Click here for an expanded range PINPOINT® Salinity chart.

Koi and Freshwater Systems benefit greatly from a small but precise level of added salt. Typically, a 0.3% level is considered optimum. These low levels can only be accurately measured with a PINPOINT® Salinity Monitor. Hydrometers and refractometers are generally impossible to use at these low salt levels. The PINPOINT® Salinity Monitor should first be calibrated with a 0.3% salt fluid. Prepare this fluid by mixing 11.4 grams of pure uniodized table salt (Kosher Salt) with 3,785mL (1 gallon) of distilled or deionized water. Perhaps your neighborood pharmacist can help measure the 11.4 grams of salt. Submerge the probe into this 0.3% calibration fluid and calibrate the PINPOINT® Salinity Monitor to display 5.5mS by adjusting screw #3. Your PINPOINT® Salinity Monitor is now calibrated to read the low salt levels of a Koi pond, etc. It is important to take into account the existing salt level in a pond before adding any additional salt.

Salinity is a complex subject and one must be sure of the target specific gravity or ppt Salt has been properly selected in advance. The PINPOINT® Salinity Monitor is automatically temperature compensated therefore the displayed values are already compensated and corrected.

NOTE: Do not adjust screw #4 since this is used to set frequency and requires specialized equipment for adjustment. Screw #4 has been set at the factory and does not require further adjustment. A small amount of glue has been placed on screw #4 to prevent accidental adjustment.

Important Points to Remember

• The PINPOINT® Salinity Meter is NOT waterproof and must be operated on a dry surface. Any liquid contact on the printed circuit board will cause corrosion and void warranty.
• It is important to "swirl" the probe so as to eliminate any air bubbles that may accumulate under the probe before taking a measurement.
• The probe is epoxy sealed and can be totally submerged.
• The electrode should be cleaned every few months with a mild solution of water (16 oz.) and dishwashing detergent (1/2 teaspoon). Rinse the electrode well with fresh water.
• The PINPOINT® Salinity Monitor is automatically compensated throughout the temperature range 32ºF to 122ºF (0º to 50ºC).
• Calibrate the monitor with the appropriate fluid before use.
• Check the calibration occasionally. Calibration fluid can be re-used if uncontaminated by other fluids and kept in a tightly capped container.

Reference Chart Sources:

1. Zerbe and Taylor (1953)
2. Cox R.A., The Physical Properties of Seawater, Chemical Oceanography, Vol. 1, Riley, J.P. and Skirrow, G. Eds., Academic Press, London, 1965.