4 Reasons Users Opt For Ultrasonic Clamp-on Meters Over Insertion Electromagnetic Meters

Insertion electromagnetic meters have no moving parts, requiring lower maintenance during operation. However, one major drawback of these popular meters is the need for drilling during installation. Users must stop operations, drill a specified hole into the pipe and fit the meter to ensure proper installation and function. If facilities don’t have experienced staff on hand, they may need to hire an outside contractor to install the meter—which adds to the installation cost. Altogether, this process takes upwards of 2 hours and costs hundreds, if not thousands of dollars, for each installation location.

Ultrasonic technology has become another leading option in most heating, ventilation and air conditioning (HVAC) applications. Discover key reasons why users choose meters like our Dynasonics^® TFX-5000 Ultrasonic clamp-on meter instead of insertion electromagnetic counterparts.

1. Unmatched Accuracy

Ultrasonic clamp-on meters are inherently accurate with an impressive accuracy of reading of ±0.5% and a repeatability performance of ±0.2%. They maintain accuracy across a wide range of flow applications and have a greater extended low flow accuracy compared to mechanical meters. Using transit time technology, these meters can sample the flow profile 80 times per second, providing high-resolution flow data for stable and repeatable readings. And because there are no moving parts to impede the flow stream, these meters do not shed vortices—which can shake and damage the flow meter probe, compromising meter readings.

In contrast, insertion electromagnetic meters often offer an accuracy of reading of ±1.0%. Although this is still a fair accuracy rating, that extra 0.5% can make all the difference—especially in low flow applications where accuracy is critical. Additionally, these meters only sample a small portion of the flow profile due to their insertion design, which has a flow sensor located toward the bottom of the insertion probe. As water flows past the flow sensor, it can generate eddy currents, defined as electrical current loops induced within conductors by a changing magnetic field. These currents can cause inaccurate meter readings.

2. Simplified Installation

There’s no comparison when it comes to installation between an ultrasonic clamp-on meter and an insertion electromagnetic meter. Ultrasonic clamp-on meters are no longer only for retrofit projects. They are accurate, permanent solutions. These meters are easily installed on a pipe’s exterior by a single user in under an hour. This lowers overall startup time and installation costs so users can begin capturing critical data in a timely manner.

When installing insertion mag meters, certain meter clearances are required to place the meter over the valve assembly and around the pipe. This, in turn makes it much harder to find the adequate straight run with the required clearance. Installations may also call for welders and hot tap permits to ensure it was done correctly, adding to the number of people and amount of equipment brought onsite.

Hot tapping is the only way to install an insertion mag meter without shutting down operations. It’s a costly, time-consuming process that has multiple steps to assure welds are not cracked and compromised. During the hot tapping process, it’s also critical to protect against pipe shaving and pipe material entering the system. These materials can damage pumps and motors within the HVAC systems.

By choosing an ultrasonic meter, users can install and get their meter running more quickly to begin realizing a return on investment. The TFX-5000 meter eliminates the hot tapping procedure, so additional equipment and staff aren’t needed. This meter can be installed at a fraction of the time and cost of insertion mag meters.

3. Long-Term Reliability

Unlike some ultrasonic clamp-on flow meters, our TFX-5000 flow meter uses silicone to connect flow transducers to the pipe. The silicone then hardens like hard rubber, creating a long-term acoustic coupling that protects against moisture between the transducers and the pipe. This ensures the meter’s transducers will never disconnect from the pipe due to moisture, corrosion, evaporation of acoustic gel or hardening of boots placed around the transducers. These ultrasonic meters have no O-rings, seals or leak paths of any kind to monitor, maintain or replace, which provides long-term reliable operation.

Insertion mag meters are installed in a pipe and dangle into the flow stream. As a result, the meter can easily collect dirt, debris and other particulates in the pipe and coat the electrodes, requiring cleaning over time. Additionally, debris can enter the pipe when drilling for installation.

4. Technological Advancements

Ultrasonic meters offer multiple communications with capabilities already built into the unit. In contrast, insertion mags require users to buy additional equipment to view flow rate and British Thermal Units (BTUs) and send flow data total performance into the Building Management System (BMS) or programmable logic controller (PLC). Plus, ultrasonic meters feature a large local display or digital read right on the meter to simplify processes even more.

Choosing a Meter for Your Application

Whether you’re capturing a flow measurement baseline for your university’s energy audit or installing permanently on your HVAC system to optimize performance, ultrasonic clamp-on meters offer many leading benefits that make them the right choice for a vast majority of applications. Learn more about how this technology works and why it’s the meter of choice for building design, HVAC and plumbing applications.