Set overfill probe correctly to ensure safety

Feb. 1, 2004
CORRECTLY setting the overfill protection system probe in petroleum tank trailers is essential in order to reduce the risk of a product incident, said

CORRECTLY setting the overfill protection system probe in petroleum tank trailers is essential in order to reduce the risk of a product incident, said Jeff Hunter of Civacon.

There are several factors to consider in determining the setting, including the bottom loading flow rate from the terminal. At 900 gallons per minute, the shutoff system may take as long as four seconds to respond.

“Look at the manufacturer capacity chart in inches and the tables that they provide, and translate gallons into inches to decide where the probe is to be set,” Hunter said.

On a related a subject, he addressed crimping methods for overfill sensors and wiring that connect those to the sockets.

Poor connections lead to non-working or intermittent responses on fill detection systems. He said a hand-crimping tool can be used for stripping wire, but has few advantages. The disadvantages are that it is hard to create a quality crimp.

The use of a ratchet crimp tool is better. It has a mechanism inside so that when the process is started, an entire process is completed before the crimp is accomplished. Once the process is begun, the jaws won't open until the crimp is completed. “It's a little more expensive, but it's worth it,” he said.

He recommended that only a non-corrosive grease be used in the process. He also pointed out that sockets should be clean and covered when not in use.