Woodward 2301E-HT, Руководство по эксплуатации продукта

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Manual 35092 2301E-HT Hydro (Francis Turbines)
Woodward 27
When the gate 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 gate keeps above the High set
point for the High Delay Time and it will be reset if the gate keeps below the Low set point for Low Delay
Time.
When the gate 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 gate keeps below the Low set point for
the Low Delay Time and it will be reset if the gate keeps above the High set point for High Delay Time.
Example of a gate position switch setup: A gate position switch is desired to turn on a light when the
gates are closed. Configurable relay #1 (or #2) is configured as gate position switch #1. The gate position
switch is configured as a decreasing switch. The Low set point is adjusted to 1%, setting this switch
slightly above zero will take care of any drifting calibration of the gate position transducer. It is decided
that the switch should reset at 4% gate position, so the High set point is adjusted to 4%.
kW Switches
There are two kW switches that can be used in one of the configurable relays outputs. All kW switches
are also passed along to Modbus.
The kW switches can be configured as increasing switches or decreasing switches. This means that the
relay energizes as the unit kW is increasing above the set point for a determined time or decreasing
below the set point during a determined time. Each kW switch has a High set point, High Delay, Low set
point and Low Delay.
When the kW 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 kW keeps above the High set
point for the High Delay Time and it will be reset if the kW keeps below the Low set point for Low Delay
Time.
When the kW 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 kW keeps below the Low set point for
the Low Delay Time and it will be reset if the kW keeps above the High set point for High Delay Time.
Baseload Control
When the unit is in parallel with the grid it may be desired to put it into Baseload control. In this mode the
unit will assume a fixed amount of load given by the Baseload Reference. In order to perform that action
the the CTs and PTs must be correctly connected to the controller and a PID that compares the actual
load with the Baseload Reference in order to generate a speed setpoint to the controller will do this
function. At the moment that the Baseload mode is enabled the load reference ramps to the “Initial
Baseload Reference” at a configurable rate.
The initial baseload reference can be set from an internal value configured under the service menu or can
be a Modbus value. This can be chosen only from Modbus. If Modbus communication is lost, then the
internal value is automatically selected.
After that, the baseload reference can be raised or lowered by the Raise and Lower inputs, respectively.
A Remote Baseload Reference can be used as well. There are two ways to enable the Remote Baseload
Reference: closing both the Raise and Lower inputs when in Baseload Mode, or by enabling it via a
Modbus Command. The remote baseload reference can either come from a 4
–20 mA analog input or
through Modbus communication.
If there’s a failure in the Remote Baseload signal the remote baseload control is automatically disabled
and an alarm is given.
When the baseload control is disabled the control tracks the generator load and maintain it, making a
bumpless transfer between the baseload mode and the other control modes.
Released