Woodward 505HT, Инструкция по установке и эксплуатации

Страница: 61 / 199

Manual 35116 505HT for Pelton Turbines
Woodward 59
The nozzle average demand switches can be configured as increasing switches or decreasing switches.
This means that the relay energizes as the nozzle average demand is increasing or decreasing compared
to the set point. Each nozzle average demand switch has a High set point and a Low set point. When the
nozzle average demand switch is configured as an increasing switch, the High set point is the trip point
and the Low set point is the switch’s reset point. When the nozzle average demand switch is configured
as a decreasing switch, the Low set point is the trip point, and the High set point is the reset point.
Here is an example of a nozzle average demand switch setup: A nozzle average demand switch is
desired to turn on a light when the nozzles are closed. Configurable relay #1 is configured as nozzle
average demand switch #1. The nozzle average demand switch is configured as a decreasing switch.
The Low set point is adjusted to 1. It is decided that the switch should reset at 4% nozzle average
demand, so the High set point is adjusted to 4%.
A failsafe logic is available in case all nozzle feedback signals fails. If this failsafe logic is used the
referred output can be forced to a “Fail Safe State” for the “Time to Disable Fail Safe”, expressed in
minutes. After the “Time to Disable Fail Safe” time expires the switch output gets back to its natural state.
If a turbine start command is issued the failsafe logic is disabled automatically.
See Appendix F, Figure F-7 for additional detail on Nozzle Average Demand.
Active Power Switches
There are four active power switches that can be used in one of the configurable outputs. All active power
switches are also passed along to Modbus.
The active power switches can be configured as increasing switches or decreasing switches. This means
that the relay energizes as the unit active power is increasing above the set point or decreasing below the
set point. Each active power switch has a High set point and a Low set point. When the active power
switch is configured as an increasing switch, the High set point is the trip point and the Low set point is
the switch’s reset point. When the active power switch is configured as a decreasing switch, the Low set
point is the trip point, and the High set point is the reset point. There are also configurable delays for
activation and deactivation of the switches.
Here is an example of an active power switch setup: An active power switch is desired to provide a
permissive for opening the generator breaker when the unit reaches 3% rated active power. Configurable
relay #1 is configured as active power switch #1. The active power switch is configured as a decreasing
switch. The Low set point is adjusted to 3%. It is decided that the switch should reset at 5% rated active
power, so the High set point is adjusted to 5%.
A failsafe logic is available in case the power transducer signal fails. If this failsafe logic is used the
referred output can be forced to a “Fail Safe State” as long as this signal failure remains. When the signal
gets back to normal the switch gets back to its natural state.
Shutdown Datalog
The control provides a shutdown datalog with its relevant Boolean and analog variables. At the moment
the turbine starts the datalog starts collecting data on a circular buffer. When the buffer is full the new
data overwrites the old one in a first-in-first-out method. When a shutdown occurs the datalog still collects
some data after it and then prints a file called TURBDAT_x.log, where x is an index that varies from 1 to
4. Therefore it will store the datalog files from the last four shutdown for later analysis. These files can be
retrieved using a Woodward software called App Manager and can be opened/analyzed using Control
Assistant.
Released