Tech Blog

Across the United States, aging transportation infrastructure continues to challenge civil engineers and public agencies. Increased traffic volumes, heavier freight loads, and decades of wear have forced many bridges to operate under load restrictions, raising concerns about long-term structural integrity and public safety.

While there are many sensing technologies to measure linear (straight-line) position or displacement (as opposed to micro position sensing such as strain gage, capacitive, or laser technologies) most are not suitable for use in environments known to be “Hazardous Locations”, commonly referred to as “Hazlocs”. So, what are “hazloc” areas? The answer is both simple and straight-forward, but with several nuances.

LZ-19 UL Approved for Hazlocs

For analog sensor data transmission, a 4-20 mA current loop is a very common method to convey the sensor data acquired.

Periodically the need arises to be able to measure the primary impedance of an LVDT to ensure that it will work with a particular version of signal conditioning electronics. Typical LVDT signal conditioner systems are built to work with a primary impedance of 200 Ohms or higher, but some systems cannot supply enough excitation power to operate an ordinary industrial LVDT.