Smart Solutions Category: Building Automation/Energy Management Systems

Predictive Maintenance Streamlines Operations

With the nClarity predictive maintenance (PdM) platform, Mazza Mechanical transitioned from the traditional preventive maintenance model to a digital-based service, streamlining business operations considerably. Mazza Vice President Ledgie DeRose explained, “We are now able to get early warnings when issues emerge without having to go onsite. This is far more productive than our old approach of dispatching techs 12 times per year.”

Ledgie DeRose continued, “In the event we feel the need to dispatch techs, they are far better prepared with a precise diagnosis, optimizing our time onsite and reducing callbacks. It’s always great when a tech gets onsite before the customer even knows there is an issue.”

Meeting Customer Demands

Brothers Dan and Ledgie DeRose, president and vice president of Mazza, respectively, and their team service some large, innovative manufacturing clients who expect continuous innovation from their partners. Manufacturers are seeing the industrial sector’s evolution to a digitized PdM model, so it was inevitable that Mazza would feel some pressure to migrate to a PdM service model.

Using Pulse circuit boards connected to sensors that monitor key metrics in each HVAC unit, the nClarity technology captures and analyzes operations, which Mazza service operations personnel use to anticipate maintenance needs.

The DeRoses began engaging clients in discussions regarding the impact the nClarity technology could have on their operations. The real motivator for most clients was the emphasis on system monitoring integrated into their service operations that drives measurable uptime.

“Our clients are sophisticated operators that understand the value of data in their businesses. Approaching them with a platform that collects machine-level, real-time data that is processed through purpose-built analytics that detect sources of machine degradation and potential failure really addressed a need,” said Dan DeRose.

Package units that service critical areas were targeted in several facilities. Mazza techs installed Pulse circuit boards at each HVAC unit and connected sensors from the Pulse to key components inside each unit (capturing information on supply and return air, high and low side pressure, and temperatures). An onboard, utility-grade meter was connected via a current transformer to unit power. Ledgie DeRose estimated installation took about two hours per unit.

One-minute interval data are routed from each Pulse to a private cellular network (no IT needed), which is then forwarded to nClarity’s service operations analytics engine in the cloud. Ultimately, building insights (i.e., robust alerts) are pushed to service operations dashboards and mobile applications that act as a digital gauge. Service operations personnel are all able to remotely access machine data.

“While a lot of our customers have invested in sophisticated controls, we are convinced implementing a monitoring solution is really what our customers are looking for to meet this need.”

—Ledgie DeRose, Vice President, Mazza Mechanical

“While a lot of our customers have invested in sophisticated controls, we are convinced implementing a monitoring solution is really what our customers are looking for to meet this need,” said Ledgie DeRose. “If we tried to do this with controls, it would be way too complicated, expensive, and not as usable by my service ops team.”

This nClarity article highlights the sales advantages of real-time HVAC monitoring devices: https://www.nclarity.com/blog/the-unfair-sales-advantage-of-iot-based-real-time-hvac-monitoring

A Win-Win Situation

Dan DeRose said, “We are really encouraged by the impact this data is having on our teams and our clients. Even in its early stage, it’s easy to see the value of a predictive service model.”

Mazza is now exploring additional benefits for clients and looking for areas that can drive further productivity gains. “From conducting ‘pre-PMs’ (prioritizing units based on performance before doing onsite preventive maintenance), to engaging in performance data-centric asset planning, to measuring energy consumption with the Pulse’s onboard power meter, we are excited to enter into the next phase of this transition,” said Dan DeRose.

For more information, visit www.nclarity.com/contractor.

Siemens Provides Contractor Tips on Selecting Damper Actuators That Make the Most of HVAC Systems

In recent years, HVAC trade magazines have cited that more than one third of the commercial HVAC systems in the United States are broken. They also point out the poor state of HVAC equipment across much of the K–12 market. Installing upgraded HVAC equipment and effective building control systems in new and existing buildings significantly improves occupant comfort and productivity, but it is the damper actuators that move the equipment and allow the user to deploy control strategies. Because damper actuators enable HVAC systems to deliver measurable, sustainable energy savings, Siemens offers these tips on selecting the right product for your project.

As you upgrade facilities with improved environmental building controls, check damper actuator operation to ensure you maintain your system’s energy savings. If you need to replace the actuator, consider the following:

  • How much torque is required to move the equipment?
  • For retrofits or new installations, how much torque is required from the actuators?
  • What are the characteristics of the HVAC system?

The size, quantity, and ultimate selection of actuators required depend on the factors below:

  • Type of damper seals (standard, low, or very low leakage)
  • Number of damper sections
  • Approach air velocity
  • Static pressure
  • Control signal and other features required for operation
  • Quality and environmental operating conditions of the damper installation

Calculating Torque Requirements

Follow these steps to determine how much torque is needed to move the equipment:

  1. From the damper or equipment manufacturer, calculate the damper torque rating (DTR) for the damper at the most severe operating conditions. If it is not available, use the table below to estimate the leakage type, static pressure, and air velocity.
  2. Calculate the damper area (DA) in square feet (L×W) from the damper dimensions.
  3. Calculate the total damper torque (TDT) in pound-inches using the following formula: TDT = DTR × DA.
  4. Apply a safety factor to that torque (20 percent more than the calculation determined is advised).

Damper Actuator Selection Criteria

Given the required torque, decide the following damper actuator selection criteria:

Does the equipment need to close in the event of a power loss to stop cold air from entering the building or freezing other equipment?

If so, then a spring return (SR) actuator is needed where a physical spring or another mechanism like capacitors move the actuator/equipment position to the closed position in the absence of power. If the answer is “no,” damage to the equipment or building will occur in the event of a power failure, as in the case of an interior space, and a fail-in-place or non-spring return (NSR) actuator can be used.

What input power will the actuator need to operate: 24 VAC, 24 VDC, or 120 VAC? What type of control is needed for the equipment/application: two-position (open/closed), floating control, or modulating the equipment in signals of 0–10 VDC voltage or 4–20 mA current signals?

Once voltage and signal requirements are understood, determine what size connection is required to operate the equipment. A self-centering shaft adapter connection is especially useful when high torque actuation is required and provides many advantages over other shaft connection methods:

  • Save installation time through quick connection to the equipment shaf
  • No call-backs from slipping shafts
  • Long life and successful operation on a wide range of equipment shaft sizes

Other features to consider include using low-voltage plenum-rated product when local codes allow plenum-rated actuators to be installed without the need for conduit, saving cost and eventual metal disposal concerns. When proof of equipment closure is required, built-in dual adjustable auxiliary switches not only save time by eliminating a complicated installation but also can be set in five-degree increments for maximum control system adaptability. Also, consider protection of the actuator from outdoor elements and the connection methods needed when you cannot connect directly to the equipment shaft.

Finally, ensure the control system is deploying an efficient control strategy to the equipment and actuators in operation.

For more information, visit www.usa.siemens.com.