Threshold and Duration Rules for Plant Alarms
Rules combine high and low limits, how long a condition must last and how fast a value is changing. The supervisors who receive the alarm set them, and every change is recorded.
Why a bare limit is not enough
A plain high limit sounds the hooter each time a door is opened. Supervisors learn to ignore it, and an alarm that matters then arrives unnoticed. Duration separates a door opened for forty seconds from a fault that lasts nine minutes.
What a rule can say
How the numbers get chosen
Limits and durations are agreed with your supervisors, then tuned during a parallel run until the real events fire and routine ones do not.
- The people who receive alarms set what counts as abnormal
- Each device carries its own range and its own duration
- Rules run on the gateway at the site, not only in the cloud
- Every excursion outside range is kept with its duration
Frequently asked questions
Who decides the limits?
Your supervisors and maintenance in-charge, because they know how the machine behaves in normal running. GullySystem supplies the screen and the questions during set-up. The limits stay with you.
Can a threshold differ by shift?
Yes. A cold room loaded at dawn behaves differently from the same room at midnight, and the duration can reflect that. Rules are set per device and per shift.
Will the rules still work if the internet is down?
Yes, because they run on the gateway at the site. The hooter still sounds and an interlock still fires. Readings are held locally and fill into the history once the link returns, with their original times.
Tell us what you need.
Share your requirements and one of our engineers will come back to you within one business day.
- No obligation
- A reply within one business day
- Your details stay private
Start with your requirements
Seven short steps that tell us what you need. An engineer reads them before getting in touch.
Share your requirements