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PosiTector SST Soluble Salt Tester

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Video Transcript

Introducing the new PosiTector SST Soluble Salt Tester from DeFelsko- the Measure of Quality

Before the application of protective coatings, steel substrates must be carefully cleaned. The surface should then be tested to determine if the level of salt contamination is acceptable or not.

Soluble salts are not visible to the naked eye. If allowed to remain on the substrate in sufficient quantities, they can draw moisture through the coating causing premature coating failure from osmotic blistering or disbondment.  

The test for water-soluble salts is done in accordance with ISO 8502-9.  As a part of that method, the extraction of soluble salt contaminants for analysis is performed in accordance with ISO 8502-6 — the Bresle method.

Put simply, the Bresle method involves placing a volume of water in a chamber against the surface. This water dissolves soluble salts present on the surface, raising the conductivity of the water. The measured increase in conductivity establishes the concentration of soluble salts.  

The PosiTector SST conductivity probe, when used in conjunction with either the Bresle Method PosiPatch or Bresle Method DeFelsko Patch, vastly simplifies the process of measuring soluble salt contamination. It represents a simpler and easier way to use the Bresle method. Like all DeFelsko products, each kit contains everything you need to start measuring.

When connected to a PosiTector body, the PosiTector SST conductivity probe guides users through the three simple steps required to take a conductivity measurement.

It features a purpose-built test cell, optimized for the range, resolution, and test volume of the Bresle method. A built-in temperature sensor compensates the reading for accuracy, and records the sample temperature during each measurement.

The change in conductivity and the surface density of salts is automatically calculated, displayed and saved into memory for further reporting with DeFelsko’s suite of PosiSoft software solutions. There is no need for math, unit conversions, or adjustments for volume and temperature. The test time is automatically measured and stored.

The PosiTector SST probe is factory calibrated, and includes a Long Form Certificate of Calibration traceable to NIST.

When ‘Bresle Mode’ is deactivated, it becomes a regular conductivity meter making it ideal for testing abrasive materials in accordance with ISO 11127-6 and ASTM D4940.

While the PosiTector SST probe can be used with any test patch, there are numerous advantages to the Bresle Method DeFelsko Patch, and the revolutionary PosiPatch.

The DeFelsko Patch is low cost, latex-free, and works on nearly any surface geometry. It features a low-tack adhesive, which creates a tight seal while remaining easy to remove without leaving behind any foam residue.

The revolutionary DeFelsko PosiPatch further simplifies the Bresle method. It is functionally equivalent to the Bresle Patch, but requires no adhesive, as it is held against the surface by a magnetic holding ring. It has a built-in port which allows fluid to be injected using a dull polypropylene dispensing tube, eliminating sharp needles from the test. It features a patented air-permeable membrane, which automatically releases trapped air as water is injected, then agitates the water as it is withdrawn. It is also reusable, and a single PosiPatch can be used for multiple tests.

Using the PosiTector SST with either test patch is quick and easy. The first step is to acquire a background conductivity measurement.

First, pour at least 4 milliliters of deionized water into the cup, to prevent contamination of the water source.

Fill the syringe with deionized water from the cup

The PosiTector automatically displays the previous background measurement. Press the minus button to use it.

To take a new one, fill the test cell with water.

Press the plus button to save the new background measurement.

Draw the water back into the syringe, removing all of the solution from the test cell.

Invert the syringe, and expel the air and excess solution until there are 3 milliliters of solution remaining in the syringe.

If using the Bresle Method DeFelsko Patch, remove the backing and foam center from the patch, taking care not to touch the interior.

Press it firmly onto the surface making sure most of the air escapes.  

Pierce the top of the patch at the foam perimeter, allowing the needle to penetrate into the center of the patch

Inject roughly half of the water into the patch. Then, withdraw the air from the patch.

Remove the syringe from the patch and expel the air. Inject the rest of the water into the patch

If using the PosiPatch, begin by placing it into the magnetic ring, taking care not to touch the interior.

Place the magnetic ring on the surface, and inject the water into the patch using the port. The air within the patch automatically escapes through the air-permeable membrane.

Once the water is injected into either patch, press the plus button to start the test timer.

Use the syringe to repeatedly inject and withdraw the water. ISO 8502-6 recommends that this process be completed at least four times and that the test time be agreed between the interested parties. Often, two minutes is sufficient.

After the desired amount of time has elapsed, withdraw the water from the test patch

To complete the measurement, inject the water into the test cell of the PosiTector SST, and press the plus button.

The initial background measurement is automatically subtracted from the final reading, and the test results are displayed in units of micro Siemens per centimeter and milligrams per square meter along with the test time and sample temperatures, information required by most standards.

Press the plus button again to begin a new test. All results are stored in memory if that option is selected.

The patch can now be removed from the surface. The Bresle Method DeFelsko Patch peels off the surface easier and with less residue than conventional Bresle patches. It is disposed of after the test.

The PosiPatch lifts cleanly off the surface, with absolutely no residue. The user may choose to discard the PosiPatch and begin the next test with a new one. Or they may choose to simply rinse with DI water and reuse for several more tests until worn.

Once a reading is saved into the PosiTector memory, four free PosiSoft software options can manage data and create professional reports.

PosiSoft USB Drive is a simple gage interface to retrieve data and pre-formatted reports in a manner similar to a usb flash drive.

There is no software to install or internet connection required.

PosiSoft Desktop is a powerful application for viewing and archiving measurement data with no internet connection required.  Easily create custom professional PDF reports. brings the intuitive interface of PosiSoft Desktop to the cloud.  Wirelessly synchronize data from your PosiTector Advanced gage directly to the cloud.

The PosiTector App connects an android or IOS mobile device to your PosiTector Advanced gage allowing you to create and email reports from the job site.  Together the PosiTector SST Soluble Salt Tester, Bresle Method Patch options and PosiSoft Software streamline and greatly simplify the Bresle method.

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