Are they resistant to caustic chemicals?
Yes. Our standard model, the PT-500, is made with 316L stainless steel. We're also testing a new PVC model, the PT-503. Between the two of them, they cover a lot of chemicals, both inert and caustic. If you're interested in testing our upcoming PT-503 PVC model, contact our sales department.
How do I protect against electrolysis?
Electrolysis is a chemical reaction to current running through your liquid. This is the unfortunate result of a ground loop - when multiple grounds have a difference of electrical potential and create a flowing current between them. You have two options to eliminate electrolysis:
  • Get rid of the ground loop
  • Use a plastic material, instead of a metal

To get rid of the ground loop, you'll need to ensure that your sensor is only attached to a single ground. The electrolysis is probably happening because the submersible sensor is case grounded to the liquid around it, and the current is flowing from the sensor housing to the nearest ground point. All you have to do in this situation is to disconnect the ground wire of the sensor at the wiring terminal inside the control box.

If this makes you nervous, then you can always test our upcoming PT-503 PVC submersible pressure transducer. This sensor is currently in a BETA release, and is appropriate for testing purposes only. Contact our sales department to learn more.

Do you have lightning protection?
Yes. Lightning protection is built right into the Series PT-500 with reverse polarity and surge protection per IEC 61000-4-5. Most others require external surge protectors ($300+) to provide the same protection.
What is the max depth?
For the Series PT-500l, it's 450 ft. If you are testing the PT-503, it's 346 ft. The Series PT-510 and Series PT-510W top out (bottom out?) at 46. This is not a limitation of the sensing elements and diaphragm, but of the sensor housing.
How do you protect the diaphragm?
We have two good options for protecting the diaphragm:
  • Nose Cone
  • Cage

Typically, the nose cone is sufficient. However, in turbulent or high flow environments with suspended solids, the cage is recommended.

What is a vent tube and why is it important?
The vent tube is a component of a vented (psig) submersible pressure transducer's cable that vents the chamber behind the diaphragm to atmospheric pressure. This is critical to the operation and accuracy of the sensor. The sensor's reference point is atmospheric pressure, meaning it automatically adjusts to changes in atmospheric (barometric) pressure - or that it tells you how much pressure is applied to the sensor in addition to atmospheric.

It's important to keep the vent tube both dry and unobstructed. We offer two options for keeping the tube dry: a desiccant cartridge and a hydrophobic, breathable vent cap. Make sure you have one of these installed on your vent tube to keep the sensor's electronics safe.

Blocking or obstructing the vent tube is also detrimental. If the sensor is not properly vented, then accuracy will suffer as the atmosphere's pressure will begin to change the way the sensor's diaphragm behaves. Sealing off the vent will fix the sensor's reference point to one pressure, leaving it vulnerable to changes in elevation and weather. As submersible pressure sensors are typically low pressure instruments, these small changes in the atmosphere can have a noticeable affect on your level reading.