Alarm Trips: The Ups and Downs
A limit alarm trip monitors a process signal (such as one representing temperature, pressure, level or flow) and compares it against a preset limit. If the process signal moves to an undesirable high or low condition, the alarm activates a relay output to warn of trouble, provide on/off control or institute an emergency shutdown.
While limit alarm trips are best known as a sure way to activate a warning light, siren or bell when a process problem occurs, they are also called upon to do much more. In fact, today’s highly flexible and versatile alarm trips can be found working in a wide range of applications, under an impressive list of pseudonyms.