ESL’s UL Listed patent pending eTRUconnect™ PS Series provides safe utility shore power to electric or hybrid refrigerated units on truck trailers, eliminating emissions while loading/unloading or idle. Connecting electric or hybrid refrigerated units to shore power eliminates the need of running onboard diesel generators/engines to keep the cargo within the optimal temperature range. This results in significant savings attributed to much lower electric energy cost. eTRUconnect’s, safe and simple connection and disconnection procedure allows truck operators to use the system while minimizing the risk of injury and the liability to the facility owner. ESL’s eTRUconnect is the ideal solution for distribution centers, warehouses, grocery stores and truck stops. Watch our video to learn more!
Author: Erika Thorson
ESL’s Holiday Video 2019
Santa is over-worked. Too many people, not enough time. The elves have a plan to help update Santa’s Naughty or Nice List. What could possibly go wrong?
Designing a Safe Reefer Connection: Part 2
Increasing safety
While little has changed in the construction of the receptacles themselves over the years, ESL is constantly challenged to find new solutions that meet unique customer safety and operational requirements. Usually terminal operators have limited or no control over the maintenance and standards associated with male plugs on reefer container cables, the quality of which varies considerably. A male plug with water and salt ingress can “flash” outwards into the operator when the interlock actuator is engaged. In order to energize a receptacle from a safe distance, ESL designed a rear-actuated receptacle that removes this safety risk by requiring the operator to engage the actuator rod from behind the assembly enclosure, out of the way in case of a flashover. Since the development of our rear-actuated receptacle, ESL has installed systems at terminals in Philadelphia, Nairobi and Vancouver. In Philadelphia, ESL added LED lights on the rear of the enclosures so operators can see they have energized the correct receptacle.
Damage control
Properly treated and maintained, a safety-interlocked reefer receptacle is designed to last many years. The reality, however, is that equipment is often damaged through misuse. In our experience, the number one cause of receptacle damage is “drive-offs”, where the reefer is moved without first being disconnected. This will destroy a nylon or plastic ROA, but not a stainless steel one. Stainless steel ROA’s can be repaired by just replacing the receptacle or swapping out a safety-interlocked outlet from another ROA. In North America, the incidence of drive-offs is such that stainless steel ROAs should be considered as an industry standard. ESL also offers microswitches in the receptacle that signals whether a container is connected, regardless of whether the reefer is energized or not. This information could be sent to the terminal operating system (TOS) and an instruction to move a reefer could be blocked if it is still connected.
If you missed part of our series focusing on operating reefers at terminals efficiently click here.
Designing a Safe Reefer Connection: Part 1
Safe reefer operations require a receptacle system that exceeds minimum standards in electrical codes.
Safely connecting and disconnecting reefer containers operating on 3 Phase 440-480v power represents one of the largest safety risks from an electrical hazard at the majority of container terminals. Reefer receptacles are designed and listed to electrical safety standards of UL and CE self-certification, but these only “certify” that the receptacle can carry the required electrical load. Other standards, such as IEC 60309-1 and 60309-2 cover configurations of the plug and receptacle and ensure compatibility. It is widely accepted that dealing with 480v, 32A supply presents a safety (and liability) risk and that the standard is to have interlocked connections. A safety interlock is a mechanical or electrical device that prevents a receptacle from being energized unless the male plug is properly engaged and disconnects the power supply automatically as the plug is removed. Although the safety interlock design prevents operators from “making” or “breaking” under load, it is not required under electrical codes and in some cases, terminal construction contractors look to install non-interlocked receptacles, which pose a higher safety risk to operators, but offer cost savings. Some situations arise where contractors facing strict budgets try to install non-interlocked receptacles. The objective is to make sure interlocked receptacles rather than “complying” receptacles are specified when projects are tendered. As far as the design of the interlock is concerned, there are several options. ESL’s standard system detects the ground pin of the male plug before allowing the unit to be energized, whereas other designs interlock off the key on the side of the plug. ESL believes the ground pin is the safer option. Additionally, in some markets, plug keys are frequently “shaved off” to allow a 32A plug to mate with a 30A (non-interlocking) receptacle, meaning the 32A male plug must be replaced elsewhere in the supply chain in order to safely connect to a receptacle that interlocks at the key.
Operating Efficiently
Another important aspect of reefer power supply is designing the receptacle system so the terminal can perform reefer operations efficiently. In considering the layout of the reefer area(s), terminal management has to weigh the initial costs of installing more reefer outlet assemblies (ROAs) against the labor costs of managing cabling from fewer centralized ROAs. A reefer rack structure is typically six or seven containers wide and some operators opt for an ROA with six or seven receptacles mounted centrally. This configuration is more prone to tangled reefer cables, which present tripping hazards and the chance of disconnecting the wrong cable. Terminals with wider reefer racks may even require extension cables to reach the outer containers. Installing more receptacles per ROA is ultimately a cheaper solution, but a trend towards two and three-gang ROAs due to operational efficiencies is growing. Demand is also increasing for two LED lights, one to indicate line power is available to the ROA and a second to show that the receptacle is energized and power is flowing. If the first LED is not showing, the operator will know immediately that there is an upstream power supply problem. An available option is the incorporation of an equipment ground fault protection (GFP) device on an outlet module to isolate the effect of a phase to ground short. ESL has frequently been asked to incorporate a simple ground fault protection device that can isolate a fault at the receptacle and prevent upstream switch gear from being tripped by a short. Terminal design engineers need to take into account that reefers generate ground currents during the defrost cycle, so the GFP devices should be selected and set at a value above the defrost cycle ground currents to avoid nuisance tripping.
Read part 2 of our series focusing on reefer receptacle safety and damage control.
ESL Power Systems, Inc. Becomes 100% Employee-Owned Through Employee Stock Ownership Plan (ESOP)
After 28 years of expansion and growth, ESL Power Systems opens its next chapter
CORONA, CALIFORNIA: ESL Power Systems, Inc. has completed a transaction to become 100% employee-owned through its Employee Stock Ownership Plan (ESOP). Since its inception in the early 1990’s, ESL Power Systems has emerged as an innovative leader in the design and manufacturing of safety-interlocked electrical solutions. The Company has been owned and managed by Michael Hellmers and David Hellmers, with Douglas Roy, Carlos Valero, Pete Mehalechko, John Chaney, Jaime Hatzfeld, Tom Zinchuk and Greg Leger rounding out the management team.
According to Michael Hellmers, President, “ESL employees have always been the cornerstone of our company’s success. Our team embodies ESL’s core values and share David’s and my commitment to our business and stakeholders. Employee ownership is the next logical step to ensure the legacy of our founders carries on. David and I will continue to lead the ESL team and are confident the new structure will foster an ownership culture focused on growth and customer satisfaction.”
ESL Power Systems was advised by AmbroseAdvisors, a national investment banking firm specialized in employee-ownership transitions. Michael Harden, Senior Managing Director, stated “Michael and David’s goal was to secure a sustainable future for the Company in a way that would be highly beneficial to the employees, customers, suppliers, and the community in addition to themselves. Employee ownership, done right, benefits all stakeholders and should be celebrated. We heartily congratulate the ESL team and thank them for trusting AmbroseAdvisors to manage this transition process.”
About:
ESL Power Systems, Inc. is a leading electrical equipment manufacturer for industrial and commercial applications for a variety of industries.
About: AmbroseAdvisors is a national middle-market investment bank and financial advisory firm focused on guiding and assisting business owners with ownership succession planning, primarily through employee ownership. http://www.AmbroseAdvisors.com
###
For a formal press release click here.