Woodward 2301E-HT, Руководство по эксплуатации продукта

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Manual 35092 2301E-HT Hydro (Francis Turbines)
Woodward 26
Overspeed Test
When the overspeed test is enabled, the electronic overspeed trip is disabled , the isochronous speed
reference ceiling is raised to 200%, and the raise/lower rate on the isochronous speed reference is
increased to 10% per second. To enable this test the “MECH OVERSPD TEST” [TRUE *FALSE] must be
tuned from false to TRUE. This is found under the SPEED category in service. This mode has a 30
minute timer on it to prevent it from being accidentally left enabled.
To perform the overspeed test, the test must be enabled and the unit must be running off-line. The speed
reference must be raised until the unit trips from the
mechanical overspeed . The mechanical overspeed
should be wired in series with the ESD (Emergency Shutdown) input string so that an ESD is issued to
the control. If the mechanical overspeed device does not trip the unit, the speed reference will have to be
manually lowered or the unit can be tripped manually. When the test is complete, tune “MECH OVERSPD
TEST” [TRUE *FALSE] back to FALSE.
When this test is performed, there is NO internal overspeed
protection in the 2301E-HT control. If the mechanical overspeed
device does NOT trip the unit, the speed reference will have to be
manually lowered or the unit can be tripped manually.
To prevent possible serious damage or injury from an overspeeding
engine, be prepared to make an EMERGENCY SHUTDOWN when
performing this test, to protect against runaway or failure of
mechanical or other secondary overspeed devices.
Speed Switches
There are three speed switches that can be used in one of the configurable relays outputs. All speed
switches are also passed along to Modbus.
The speed switches can be configured as increasing switches or decreasing switches. This means that
the relay energizes as the unit speed is increasing above the set point for a determined time or
decreasing below the set point during a determined time. Each speed switch has a High set point, High
Delay, Low set point and Low Delay.
When the speed switch is configured as an increasing switch, the High set point is the trigger point and
the Low set point is the switch’s reset point. The trigger will be triggered if the speed keeps above the
High set point for the High Delay Time and it will be reset if the speed keeps below the Low set point for
Low Delay Time.
When the speed switch is configured as a decreasing switch, the Low set point is the trigger point, and
the High set point is the reset point. The trigger will be triggered if the speed keeps below the Low set
point for the Low Delay Time and it will be reset if the speed keeps above the High set point for High
Delay Time.
Example of a speed switch setup:
A speed switch is desired to turn on the unit’s exciter when the unit
reaches 90% rated and keeps at this value for 5 seconds speed after a startup. Configurable relay #1 is
configured as speed switch #1. The speed switch is configured as an increasing switch. The High set
point is adjusted to 90% and the High Delay is configured to five. It is decided that the switch should reset
at 80% rated speed instantly, so the Low set point is adjusted to 80% and the Low Delay is configured to
zero.
Gate Position Switches
There are two gate switches that can be used in one of the configurable relays outputs. All gate position
switches are also passed along to Modbus.
The gate switches can be configured as increasing switches or decreasing switches. This means that the
relay energizes as the unit gate is increasing above the set point for a determined time or decreasing
below the set point during a determined time. Each gate switch has a High set point, High Delay, Low set
point and Low Delay.
Released