Figure 3-7.--EPCC panel locations.
3. Discrete inputs from the SSGTG LOCOP
Again, refer to the EOSS, EOP, and appropriate
technical manuals for a detailed description of the
4. Analog inputs from the SSGTG LOCOP
operation of these systems.
Inputs to EPCC are processed by its computer to
determine if an alarm condition exists. Alarms are
SSGTG Control and Monitoring
indicated on the PDU and by an EPCC control panel
alarm indicator. At the EPCC, eight alarm conditions for
Most SSGTG control systems reside in the LOCOP
each SSGTG are displayed by specific alarm indicators.
and exciter control panel (EXCOP). The EPCC and
All other alarms are indicated by the appropriate
switchboard control stations provide only discrete
SSGTG summary alarm light above the PDU.
inputs to the LOCOP and EXCOP. The LOCOP provides
At the EPCC, there is one SSGTG summary alarm
monitoring for the gas turbine and generator, and control
LED for each SSGTG. The summary alarm light for
for the gas turbine. This includes speed control, which
the LOCOP governor uses to regulate generator output
SSGTGS No. 1 and No. 2 operate when at least one of
frequency. The EXCOP controls generator output
22 alarm conditions occur. The summary alarm light for
voltage by regulating generator field excitation. The
SSGTG No. 3 operates when at least 1 of 25 alarm
EXCOP is enabled by the LOCOP when gas turbine
conditions occur.
speed exceeds 12,225 rpm.
Any inputs to the EPCC that do not originate from
A SSGTG has sensors to allow remote monitoring
the SSGTG LOCOP are classified as direct. These direct
of its gas turbine, generator, and supporting systems.
inputs can be either discrete or analog. Direct discrete
The EPCC receives sensory information in any one of
inputs are typically received from auxiliary contacts in
the following four ways:
equipment controllers or contact switches associated
1. Directly from controllers or contact switches
with a SSGTG support system. Direct analog inputs are
received from resistance temperature elements (RTE) or
2. Directly from temperature or level monitoring
devices
tank level receivers associated with a SSGTG.
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