Alarm Annunciators STANDARD OPERATING SEQUENCES

Model

Potential Free Inputs

Potential Inputs

Alarm Annunciator

Model

Alarm Annunciators

Minilec Microprocessor Based Alarm Annunciators are designed to keep an alert and watchful eye on your plant and processes. The entire range has been designed with an insight into the modern day manufacturing plant and its future requirements. Minilec Alarm Annunciators are equipped with microprocessor-based design, super bright LED facia windows, site selectable, programmed sequences as per ISA standard and thoughtful provisions for troubleshooting and maintenance. Dynamic, Alert and Responsive… These unique advantages have helped the Minilec Annunciators to be an icon in the power T and D industry and engineering establishments in India. The world class Minilec Annunciator has made its presence felt in Overseas markets.

FEATURES

4 windows to 128 windows
Integral & Split models
Microprocessor based
Super bright LEDs for facia
Standard operating sequences
Any other custom- made sequences
NO-NC & Trip Non-Trip site selectable
Repeat relays
Supply fail annunciation / Indication
Choice of 3 window sizes
Choice of five colours
RS 232 / RS 485 Output Port having MODBUS RTU protocol or fault Input through RS 485 port MODBUS RTU protocol.

FUNCTIONS

Continuous monitoring of input parameters
Control of process through outputs and software
Data acquisition & communication
Data Storage & records through PC

ORDERING INSTRUCTIONS

Product Family Name
Model Name
Aux. Supply / Control supply voltage
No. of Inputs (Windows)
Operating sequence

FAQs

What is an Alarm Annunciator?

An alarm annunciator is a centralized visual and audible warning system that monitors multiple process conditions in a plant or facility. It provides an immediate, unambiguous indication of an abnormal or fault condition, telling an operator exactly what has gone wrong and where.

How does it work?

The annunciator continuously monitors digital input signals from switches or sensors (e.g., high pressure, low level, pump failure). When a parameter moves outside its normal range, the corresponding “window” on the annunciator activates a bright LED light and a common horn to alert the operator.

What is a "window"?

A “window” is a single alarm point on the annunciator panel. Each window has a legend (e.g., “BOILER PRESSURE HIGH”) and a high-intensity LED. Systems can range from a compact 4-window unit to a large 128-window system for complex processes.

What are "standard operating sequences"?

This refers to the flashing and acknowledgement sequence of the alarms, standardized by ISA (International Society of Automation). A common sequence is:

Normal: LED is off.
Alarm: LED flashes and horn sounds.
Acknowledge: Operator presses a button; horn silences, LED changes to solid.
Normal Return: The condition clears; LED turns off.

What does "NO-NC & Trip Non-Trip site selectable" mean?

This is a crucial feature for flexibility.

Input Type: Each point can be configured on-site to accept either a Normally Open (NO) or a Normally Closed (NC) contact signal from the field device.

Alarm Logic: It can also be set to trigger an alarm on either a “trip” (contact change) or a “non-trip” (loss of power/signal) condition. This ensures compatibility with various safety philosophies.

What is the purpose of the "Repeat Relay"?

For each alarm point, a repeat relay is an isolated set of contacts that close when that specific alarm activates. This allows the annunciator to send a signal to another system, such as a PLC, DCS, SCADA, or a remote alarm horn, for further action or logging.

What is the advantage of the MODBUS RTU communication port?

The RS485 port with MODBUS RTU protocol allows the annunciator to communicate directly with a central computer or SCADA system. This enables:

Data Acquisition: Logging and time-stamping of all alarm events.
Remote Monitoring: Viewing the status of all alarms from a control room.

Integration: Seamlessly connecting the annunciation system into a larger plant-wide network.

What is the difference between Integral and Split models?

Integral Model: The entire annunciator system (display, logic, power supply) is housed in a single enclosure.

Split Model: The display panel (with the LED windows) is separate from the main processing unit. This allows for a sleek display on the control panel door while mounting the electronics inside the panel, saving depth.

What information is needed to order an Alarm Annunciator?

To configure the correct unit, you will need to specify: