Alarm and Trip Set Point List Template
The master list of alarm and trip set points. Enter LL, L, H and HH values with range, priority and action; the sheet checks that set points are in order and inside the instrument range.
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- How to Use sheet with steps
- Template sheet, blank and ready
- Example sheet, filled in
- 104 built in formulas
- A4 landscape print setup
- Works in Excel, Google Sheets and LibreOffice
Preview of the Filled Example
This is the Example sheet from the download, so you can see exactly how the completed alarm and trip set point list looks.
Set point list
| Tag | Description | Unit | Range min | Range max | LL | L | H | HH | Trip system | Action on trip / alarm | Priority | Deadband | Delay (s) | Set point check | Remarks |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PT 1101 | Steam header pressure | bar g | 0 | 16 | 4 | 13 | 14.5 | SIS | HH: trip burner fuel valves | Critical | 0.2 | 2 | OK | ||
| TT 2101 | Reactor jacket outlet temperature | °C | 0 | 200 | 150 | 165 | DCS | HH: close steam valve TV 2101 | High | 1 | 5 | OK | |||
| LT 4102 | Storage tank level | m | 0 | 12 | 0.8 | 1.5 | 10.5 | 11.2 | SIS | HH: close XV 4101; LL: stop pump P 401 | Critical | 0.05 | 3 | OK | |
| FT 3101 | Feed flow | m³/h | 0 | 120 | 15 | 95 | None | Operator action | Medium | 2 | 10 | OK | |||
| PDT 3105 | Filter differential pressure | mbar | 0 | 500 | 350 | 300 | None | Change filter | Low | 10 | 30 | CHECK | Example of an error: HH below H |
About the Alarm and Trip Set Point List
Alarm and trip set points are among the most safety critical data in a plant, yet they are often scattered across P&IDs, DCS configuration and SIS documents. One controlled list, reviewed by process, instrumentation and operations, keeps them consistent and is the reference for configuration, loop checks and management of change.
How to fill in this template
- List every alarm and trip from the cause and effect, P&IDs and alarm philosophy.
- Enter the instrument range so set points can be checked against it.
- Fill LL, L, H and HH (leave empty if not used), the trip system and the action.
- Set priority, deadband and delay according to your alarm philosophy (for example EEMUA 191 or ISA 18.2).
- Fix every row that shows CHECK, then issue the list for configuration and loop checks.
What the formulas do
- Set point check is OK when LL < L < H < HH (ignoring empty values) and all values lie within the range.
- Counts of rows needing correction and of SIS trips.
Related tools
Frequently Asked Questions
What is the difference between an alarm and a trip?
An alarm asks the operator to act; a trip makes the control or safety system act automatically, for example closing a valve or stopping a pump.
Why add deadband and delay?
They stop nuisance alarms from noisy signals chattering around the set point.
Who approves alarm and trip set points?
Normally process, instrumentation and operations together, and changes go through management of change.
Learn more on the blog
Types of alarms in DCS every instrumentation engineer should know
A practical guide on instrumentationblog.in that explains the procedure behind this template and how engineers apply it on real plants.
Read Full Article