FIKE CORPORATION
Page 16 of 32 Fike Explosion Protection System FM 3020541
10/06 P/N E06-051 Rev. 8
24VDC
Green
Yellow
Red
5.0 OPERATION
5.1 EPC STATUS
The EPC is the central intelligence of the
EPACO system. The following tasks are
accomplished by the EPC:
Monitors all supervised circuits for wiring
faults (Open, Short, or Activation)
Two pressure detection circuits are
monitored on a 250 micro second
(0.25 msec) rate and examined for rate of
rise and threshold levels
When activation requirements are met by
the detection circuit, it activates the series
firing output within 2 milli-seconds
Communicates system status to other EPC’s
connected locally so that they can respond
within 4 milli-seconds
Communicates system status to Annun-
ciators and Relay Control Modules for user
interface
The EPC operation can be classified into three main states of operation: Normal, Trouble and Alarm. Each
of these states are described in sections 5.2.1 through 5.2.3. Exhibit 5-4 further describes other conditions
within these states in a handy spreadsheet for quick reference.
5.1.1 EPC Normal State
When power is applied to the EPC, it performs a 4 second initialization.
At the end of the initialization, the trouble LED blinks slow and the local
piezo beeps in long recurring sound. It can then enter the “NORMAL”
state if the power is of an appropriate voltage and there are no troubles
or alarms. In the Normal State the green Power LED is ‘ON’, the local
piezo is ‘OFF’, the P6 trouble and alarm relays are energized. All other
LED’s are ‘OFF’.
5.1.2 EPC Trouble State
A trouble occurs on the EPC if any one of the supervised circuits
experiences a wiring fault open or short condition, if the EPC
configuration is invalid, if the system is disabled, if a process pressure
warning level is exceeded, or if the input voltage drops below 18VDC.
In the Trouble State the yellow Trouble LED is ‘ON’, the local piezo is
‘ON’, and the P6 trouble relay is de-energized. Depending on the
cause of the trouble, the system may or may NOT be completely
functional. Each trouble should be investigated to determine the cause
and promptly fixed. Each trouble, except for remote disable, will latch
at the EPC. If the trouble is resolved, the EPC trouble can be cleared
by disabling and re-enabling via the remote disable input, by cycling of
the power input to the EPC, or by disabling and re-enabling the EPC
via the Annunciator Module (see Annunciator Module Installation and
Operation Instructions E06-053). If the remote disable is active, the
EPC will enter the trouble state. When the remote disable is returned
to normal, the EPC will automatically clear to the normal state, if no
other troubles are present, without cycling the power.
5.1.3 EPC Alarm State
When the detection circuits have exceeded the alarm conditions
required by the configuration, the EPC enters the Alarm State. In the
Alarm State the red Alarm LED is ‘ON’, the local piezo ‘ON’, the P6
Alarm relay is de-energized, and the series firing output is activated.
The alarm state is latching. If the alarm is cleared, the EPC requires
cycling of the power input to clear the alarm.
Note: The alarm state will activate the system. If the system is
reset after an alarm, it is typical to have an open wiring fault on
the Series Firing circuit, since the actuator(s) have activated.
Exhibit 5-1 Power LED
Exhibit 5-2 Trouble LED
Note: If power is cycled to
an EPC with a Fire Bus
connected all EPCs
connected to the Fire Bus
will also need to have their
power cycled simultane-
ously to restore the Fire
Bus.
Exhibit 5-3 Alarm LED
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