Lincoln Electric Prism 4, Руководство оператора

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C-5
ACCESSORIES
OPERATION & DIAGNOSTICS
NORMAL OPERATION DESCRIPTION
A Prism with thermal suppression has active protection even
during a power outage since a discharge of suppressant is
exclusively dependent on heat induced rupture of the detection
tubing. The detection tubing is routed through the filter (dirty air)
side of the filter bank. Intake and exhaust dampers are used to
contain an event and maximize the effectiveness of a suppressant
discharge. A smoke detector shuts down the fan motor and closes
the dampers if smoke or particulate due to bypass of a damaged
filter is detected in the fan exhaust but this will not trigger a
discharge since that can only be caused by heat from a thermal
event.
B. FAN/DAMPER SHUTDOWN
There are three alarm conditions that will cause the fan to shut
down and the dampers to close. The first cause is a smoke
detector alarm, the second is heat induced rupture of the
detection tubing and third a damper failing to signal that it is open.
The lower of the two stack lights (on top of the Prism ) will
activate on any thermal event alarm and give a pulsed code of the
type of alarm condition that the unit saw to cause it to shut down.
A set of pulses followed by a 3 second off time can be decoded
according to the alarm codes chart. If there are no system
malfunctions, the dampers close when the fan is turned off.
Offline cleaning initiated when the fan is shut down will delay
damper closing until the cleaning is complete.
C. DISCHARGE NOTIFICATION
Flashing of the Stack Light’s upper high intensity light indicates
there has been a suppressant discharge. A set of pressure
switches are contained in a Firetracedual pressure switch box.
The 195psi normal charge on the detection tubing keeps the
discharge switch open. A significant loss of pressure caused by
detection tubing rupture, closes the switch which triggers system
shutdown and stack light visual notification.
D. SYSTEM MALFUNCTION ALARMS
The Prism thermal suppression system monitors important
functional conditions and provides visual display of any fault by
flashing a pulsed code on the LED stack light’s lower light. There
are four coded alarms.
a. Inlet and exhaust damper alarm. Dampers are closed when the
fan is off but are triggered to open when the fan is started. After
opening, the damper’s actuator switch sends a verification signal
that they are opened. If a signal is not received within 10 seconds,
the fan is shut down and a coded flash of pulses identifies which
damper failed to open.
b. The dual pressure switch box monitors pressure in the red
detection tubing. If the pressure drops too low due to a slow leak,
it trips a pressure switch and flashes a coded pulse on the lower
stack light.
c. The smoke detector alarm triggered by smoke or particulate
bypassing the filters triggers a coded pulse on the lower stack
light.
To allow continued system operation, two of the alarms can be
temporarily bypassed using the key switch box -the smoke
detector alarm and low pressure in the detection tubing circuit.
Note the important caution statements listed in the
troubleshooting section. Damper alarms can not be bypassed
since they must be open for the fan to move air through the unit.
The discharge alarm can not be bypassed either since the cause
of this alarm must be resolved and the system reconditioned prior
to additional use. Bypass mode is identified when the lower light
on the stack light is solid red.
F. RESOLVING ALARMS
Identify the alarm using the “Prism Stack Light Alarm Codes”
table, then use the troubleshooting section to resolve alarm codes.
When you have any alarm with a coded pulse on the stack light’s
lower light, there are some ways the controls are helpful to assist
in troubleshooting. The signals for damper open switch, discharge
switch input, service pressure switch input, smoke detector input
are all digital IO inputs into modules that have LED lights
indicating the status of that input. These are located next to the
M12 cable connection for the module. Use the system wiring print
to make sure cables are connected to the correct IO module input.
Damper feedback function can be verified by manually moving a
damper (black button is a clutch on the damper actuator) and
watching the LEDs on the module to confirm the input is “seen”
by it.
It is possible to have multiple alarm conditions, but only one code
can flash at a time. Resolving one and clearing it will allow the
flashing of any unresolved alarm conditions. Resolving all alarms
must be completed before the controls will allow a normal startup.
DISCHARGE, RECOVERY AND MAINTENANCE
A. INSPECTION
In the event of a discharge of the thermal suppression system, all
components of the system must be inspected and any damaged or
compromised components replaced. Un-ruptured red detection
tubing can be reused only if there is no evidence of heat damage.
That also applies to interior detection tube fittings containing
internal seals that can be compromised by exposure to high heat.
The suppressant tank has a pressure gauge that should show zero
after a discharge. It will need to be re-charged or replaced. If there
is any evidence of high heat exposure on any system components
they must be replaced.
B. REPLACEMENT
For quick repair, it is advisable to keep a stock of red detection
tubing along with a spare suppressant tank. Replacement parts
can be ordered through Lincoln Electric. Detection tubing is the
heart of the system and special attention should be made to
replace it with the same lengths/routing/locations. Altering from
the factory installed method can affect the systems ability to
properly react to any future thermal event. The suppressant tank
can be re-charged by the manufacturer instead of discarding it.
Contact the Lincoln Electric Service Department to aid in
indentifying a certified Firetrace distributor.
E. ALARM ACKNOWLEDGE/BYPASS CONTROL
PRISM ®
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