UPS helps keep El Paso’s water supply running smoothly
Having enough water to meet the demands for the fourth largest city in Texas wasn’t the biggest challenge facing El Paso Water (EPWater) technicians. Keeping it flowing all the time proved to be a major challenge until the city found a way to prevent uninterruptible power supply problems that occurred almost daily.
The City of El Paso, which has a population of more than 800,000, is situated next to the Rio Grande River and intersects with the Franklin Mountains. The utility relies on this natural resource along with groundwater and other water management strategies to ensure a steady, reliable supply of water for a metropolitan area that’s expected to see a 40 percent population increase projected by 2040.
Hand-in-hand with its water supply strategy reputation, EPWater’s focus on customer satisfaction and reliability is paramount. Each day, the utility’s technicians and superintendents work behind the scenes to reliably produce and distribute water from the Hueco and Mesilla Bolsons and surface water from the Rio Grande. EPWater operates four wastewater and four water treatment plants. Additionally, it operates more than 300 booster, lift and transfer stations that include fresh water, wastewater, reclaimed water and storm water facilities.
Enrique Fuentes, EPWater’s Instrumentation and Control Superintendent, keeps the water flowing with his team of 12 field technicians and other staff. His recipe for success: work smarter by employing new technologies. One facet was to improve the performance of UPS systems used in remote sites.
“AC UPS related standby calls happened sometimes three to four times a week,” he says.
In 2015, Fuentes and Instrumentation and Control Supervisor Juan Rodriguez took a hard look at EPWater’s UPS and backup battery performance. The utility used a 120 V AC UPS to keep the control system up and running during power outages.
An AC UPS audit showed that these units didn’t always keep water flowing until technicians arrived to restore power to the instrumentation, controller and microwave communications. Multiple brands of UPS systems were bulky and heavy, taking up significant station space. They provided no diagnostic information about the condition of the batteries that powered instrumentation, valves, pumps or other equipment.
In the high heat and dusty conditions of the desert, batteries failed without warning, making the AC UPS virtually useless. If a station went down, water supply could be disrupted. Reserve tanks could empty or overflow.
“We had to go to the sites to determine if the AC UPS was failing,” Fuentes says. “We found at least a couple of AC UPS issues each week during the monsoon season. The system was not intelligent. It was very difficult to know if, and when, a failure occurred when we were not on site. The station could have been down for hours before we knew there was a problem.”
When a station experienced a problem, the central operator had no way of knowing the source of the issue until a site visit had been conducted. “It’s important for the central operator to know what’s going on at the site so he can send the right crew to it,” Rodriguez says. “We have capable personnel in the field, but they won’t know if it’s an electrical or other issue until they get there. We often ended up sending three guys from different departments to the station to fix the problem. By then hours have passed.”
Joe Cox of B&M Machinery did jobs for EPWater for 22 years, providing control equipment, training and service. He knew the utility had UPS problems, so he proposed a solution. Cox teamed up with Siemens UPS expert, Nick Tamizifar, suggesting a transition from 120 V AC UPS system to a 24 V DC UPS system.
The DC UPS system’s remote diagnostics capability would let EPWater know in advance of a pending battery failure. It would also reliably provide backup power to the control system, allowing a PLC to operate long enough to provide detailed diagnostic information to central operations. Information also identified the cause of the problem, letting operations send the right crew to the site, saving crucial time.
Before signing a contract, EPWater asked for a demonstration of the SITOP UPS1600 system, with backup battery power supplied by the SITOP UPS1100 for a trial period before it would be permanently installed.
“We asked them to disconnect the battery and then switch it back, Rodriguez says. “It went right back to utility mode. If I can break it in the shop, then it won’t be any good in the field. Also, I’ll give a new product a six-month trial. If it breaks, I find another supplier. It’s not cost effective to keep buying the same brand over-and-over again and then send the guys to the field to install, calibrate and connect it multiple times if it keeps failing.”
During the six-month field trial, the battery based backup system tolerated heat well without degradation, allowing for enough time to properly shutdown the operation and communicate alarm signals to central operations. Once installed, there have been no field calls for more than two years, a far cry from the constant interruptions caused by the previous UPS system. Afterhours standby service calls were also reduced significantly.
Approximately 20 percent of the facilities have backup electric generators, but they still need a UPS to provide diagnostic information and fill in when necessary. So far, approximately 20 of EPWater’s stations have been retrofitted with the SITOP UPS1600 DC UPS system.Have an Inquiry for Siemens about this article? Click Here >>