the Article - FE Moran Special Hazard Systems

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What is Your Fire Panel Trying to Tell You?
In a perfect world, the Fire Alarm Control Panel (FACP) would be a system
that only required attention during premeditated events such as a valve
being closed off for system maintenance or for inspection and testing
purposes. For many plant employees, it’s “that control box on the wall” that
nobody wants to manage. The alarm systems that control a power
generating plant’s fire protection systems can be confusing to the personnel
who do not routinely operate and maintain them.
When operators do not thoroughly understand how FACPs function and do
not know how to appropriately respond to their signals, the consequences
can be devastating. Few emergencies in a power generating plant are
more threatening than a fire condition. Fortunately, this scenario can often
be avoided by educating plant staff about how to properly utilize FACPs.
Proper employment of Fire
Alarm Control Panels helps
protect lives and assets.
Unfortunately, these critical
systems are often
underutilized or
misinterpreted because of
insufficient knowledge.
Identifying Panel Types
The first step in understanding the functionality of FACPs is identifying the
type of system that is utilized in the facility. Today’s fire protection system
control panels range from basic hardwired panels to the sophisticated
addressable/intelligent type. Variables such as hazard type, age of the system and criteria required by
the specifying engineer all influence the type of system that is employed.
Hardwired panels were the primary fire protection system controls up until the early to mid-80’s when
addressable/intelligent fire alarm systems made their entrance into the market. Hardwired systems relied
on panel mounted modules that terminated circuits from groups of similar devices, such as a cluster of heat
detectors over a Lube Oil Reservoir, or pull stations located at the egress doors from a Tripper Floor.
Additional circuits would then connect to the alarm signaling audible/visual device, sprinkler riser switches
(waterflow, tamper, low air pressure) and releasing solenoid valves, if applicable.
Comparatively, addressable/intelligent systems utilize significantly less wiring by using Signaling Line
Circuits (SLC). The SLC is the heart of the addressable/intelligent fire alarm system, communicating with
all of the input devices such as intelligent smoke detectors, addressable pull stations and relays and
signaling circuit control modules over a common pair of wires.
All of these panels perform the same basic functions, but over time the competitive nature of the market
has resulted in the evolution of FACP’s capabilities with the introduction of new functions and features.
Early FACPs performed basic functions such as: receiving alarm, trouble and supervisory signals;
activating signaling circuits; energizing relays for equipment shutdown and closing fire doors.
Addressable/intelligent systems have become markedly more powerful, capable of handling hundreds
of devices, performing complicated functions through panel programming and providing system status
via LCD screens. ∗
It is common to find a sampling of different types of panels within a power generating plant. Because
the panels may have been installed during different stages of time, it is not unusual to find everything
from small hardwired FACPs to larger addressable/intelligent FACPs in the same facility.
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Hardwired FACPs that have central processing units and modest programming capabilities can also utilize
LCD screens to display system status.
Panel Locations
The most prevalent systems that are found within power generating plants are hardwired panels
because addressable devices typically do not meet the NEMA 4, 4X or explosion-proof standards for
resistance to environmental elements and corrosion. Standard intelligent devices such as smoke
detectors or manual pull stations are ideal for installation in locations such as Control Rooms, DCS
Rooms, Switchgear spaces and offices, but are not designed for the severe environments,
temperatures, humidity and classified areas where a coal belt, turbine underfloor or transformer reside.
These harsh environments require rugged devices designed to withstand extreme conditions, which are
then wired to an interface module that is located in a controlled environment. It is possible that the
interface module is located in the same area as the FACP, or it can be housed in separate area,
requiring additional wiring to connect the interface module to the FACP. This means that it is possible
to have a powerful, addressable/intelligent panel, but all of the wiring may still originate out of the panel
as though it was a hardwired FACP.
How do FACPs Work?
The early hardwired FACPs relied on internal jumpers and relay logic to
perform any functions outside of basic general alarm, trouble or
supervisory signaling. Over time, relay logic technology has been
replaced with onboard programming through proprietary software that is
installed from the fire alarm technician’s personal computer. Using this
software, the system can be manipulated to generate a specific reaction to
various inputs. Latter generation hardwired FACPs incorporate
microprocessor controls programmed through their keypads that
incorporate basic logic programming, eliminating the need for relays and
non-supervised internal interconnecting wiring.
Managing FACPs can be
Interpreting Signals
daunting if staff members do not
In a typical day, an operator can encounter hundreds, or even thousands,
fully understand how they
of alarms in the power plant control room. The catalysts for these alarms
operate and how to correctly
vary in significance and it can be difficult to prioritize these alarms,
interpret their signals.
especially if there is not an alarm management system in place.
Deciphering FACP signals begins with understanding the basic Fire Alarm System messaging:
System Message
Visual Cue
Implications
Green Light Only
System
Supervisory
Green light
Yellow light
Primary power is on
Valve is closed
System Trouble
Yellow light
Operational issue with
the system
Fire Alarm
Red light
Initiating device has
been triggered
Examples of Triggering
Events
N/A
A Monitored OS&Y or PIV
Valve is closed, duct or gas
detector signals
Broken wire, ground fault,
failed device, battery low
voltage, loss of AC power,
loss of communications
Waterflow has tripped,
manual pull station activated,
smoke detector has sensed
smoke, remote FACP has
alarmed, Special Hazard
system Pressure Switch has
tripped
The FACP can be in any one or all four conditions simultaneously. In an ideal situation, only the green
light will be illuminated, which means that there are no active alarms, system issues or supervisory
signals on the panel. A yellow supervisory signal signifies an event such as an Outside Screw and
Yoke (OS&Y) or Post Indicator Valve (PIV) that is in a closed position or a signal from a duct or gas
detector. The other yellow light reveals system trouble and points to issues with the system’s operation
such as problems with hardware, software or the wiring from panel to field devices. It is imperative that
system trouble signals are investigated and rectified as fire alarm signals may not be received if
equipment is malfunctioning. Red fire alarm signals are the most critical alarms as they denote a
fire situation that requires immediate action.
In addition to these basic signals, higher-end addressable/intelligent FACPs can have more advanced
indicators on the panel such as: annunciate security inputs, a Special Hazard discharge indicator, a
pre-alarm signal indicator, indications for silenced signal circuits and more.
Each signal is distinct for obvious reasons and demands that it is addressed accordingly in a timely
manner. Unfortunately, service teams often arrive at a jobsite to find a FACP in alarm, trouble or
supervisory mode, with the panel having been silenced and ignored. FACP signals are designed to
mitigate risk and effectively notify staff about emergencies. Disregarding these signals thwarts the
effectiveness of the FACP and puts plant assets and lives at risk.
Why do FACP Signals Go Ignored?
The reasons that these vital signals are often disregarded are abundant but they range from
inadequately trained personnel to cryptic messaging. At times other tasks take precedence over
attending to FACP alarms because staff members do not fully understand the gravity of some of the
signals. The unavailability of spare parts for the system can also result in perpetually active alarms.
Other explanations include vague drawings, lack of cable tabs for the system wiring and incomplete or
missing operation and maintenance manuals. Some plants even bypass a relay or circuit so that
production is not temporarily interrupted.
Educating Plant Staff to Successfully Manage FACPs
FACPs are implemented as a measure of protection to inform operators of potential or impending risks.
However, when plant staff is not thoroughly educated about the functionality and associated indications
of FACPs, the systems are rendered ineffective. Plant owners rely on operators to accurately interpret
these signals and take immediate action to prevent issues from escalating. When signals do not
receive timely response or they are overlooked altogether, risk levels are elevated
Putting a training program into practice is the best way to ensure that staff will understand proper
protocol for various scenarios related to the FACP. A comprehensive curriculum should include areas
such as: understanding hazards pertinent to the environment, identifying critical FACP components,
FACP and valve operation and system programming. Whether staff simply need a review of FACP
basics or in-depth instruction is necessary, having staff that is well-versed in these areas is a long-term
investment. In the aftermath of a fire, it is too late to find out that a disaster could have been averted
had plant staff fully understood the implications of an FACP signal.
For additional information please contact:
F.E. Moran Special Hazard Systems
2265 Carlson Drive
Northbrook, IL 60062
femoranshsinfo@femoran.com
www.femoranshs.com
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