In a quest to better manage production, high alarm rates have a negative outcome: information overload. When all systems are triggering alarms, how does any critical information get through to an operator?
When Golden Grain Energy upgraded from APACS to Siemens PCS 7, Trident Automation worked with the plant to create the most customized alarm management system possible. “Our process helps the customer to better organize alarm systems,” said Nate Nutter, PCS 7 Certified Engineer, at Trident Automation. “When customers look at a process from a high level, they can start to identify which alarms are the most critical and better define their priorities.”
As part of the upgrade, Nutter and his team did a base level alarm management audit in which they determined the number of analog and discreet alarms in the old system, analyzed the values of alarms, then determined priorities and corresponding colors for a banner bar in the HMI.
“Originally our entire system was alarmed,” said Matt Dutka, production manager at Golden Grain Energy. In that environment, operators could easily be overwhelmed with alarms. By working with Trident, Dutka was able to design a system with customized tolerances for key processes.
Golden Grain Energy created fine-tuned control loops that automatically allow the system to reset. For example, if a boiler level is too low and that causes an alarm, in the time it takes the operator to react the built-in tolerance has already been triggered. “There’s a lot of added value in this step because it allows us immediate reaction. The number one part of this upgrade is Trident has given us flexibility in determining our alarm parameters,” Dutka said.
“Now instead of waiting for an alarm to happen, we can find the sweet spot for the most efficient plant operation,” Nutter said. Trident focused on giving Golden Grain a high degree of flexibility in setting tolerances. Nutter worked with the plant to establish customized tolerances for a variety of production sequences to enable/disable limitations on production ranges.
The result was safe and efficient operating conditions for ethanol production. Customized tolerances assist with preventing production values from straying too far from their desired setpoint. Catching a process variable before it gets into an alarm condition will assist with making a more consistent product as well as lessen the likelihood of a safety trip.
For operators at Golden Grain Energy, it allows them to focus on key tasks. According to Dutka, less than 5% of the plant’s tags are alarm locked (hidden). This allows for operators to quickly determine how critical an alarm is and focus on addressing the most urgent need under normal operating conditions.
The upgrade also includes an alarm logging area that includes time stamps. Plant managers can review a log of alarms and determine if the alarm is the byproduct of another step in the production process. By analyzing the data, plant managers can identify processes that need fine-tuning to bring them into the optimal operating range. The alarm log can also help identify areas that can benefit from preventive maintenance.
Trident was able to teach the nuances of the alarm system to Golden Grain operators. “There’s a lot of information being sent over the operating system,” Nutter said. “When we upgraded in phases and explained the potential of the alarm system, they started to think about how to further enhance the system to maximize efficiency.”
“For us, it feels like Trident is part of our staff,” Dutka said. “It’s like having them in the office even though they’re remote.”