This unit is model number 9907-007 in Woodward’s series of microprocessor-based Digital Synchronizer and Load Controls. This model is Woodward’s replacement for the 9905-287, which was made obsolete in 1995. The 9907-007 model is designed to be used in the paralleling, synchronizing, loading, and unloading of three-phase AC generator sets. It is one of the reduced upgrade level units in this Woodward series, and therefore does not have power factor control or process control functions.
A few of the 9907-007 functions include:
- Built in diagnostics
- Setup, metering, and diagnostic capability through a handheld programmer terminal
- Automatic generator loading and unloading
- Droop, base load, and isochronous load control capability
- Reverse power relay.
This device has a WYE PT Configuration, a +3.0 Vdc Speed Bias, and a 120/240 Vac Input Voltage. It is rated for use in operating temps from –40 to +70 °C (-40 to 158 F) and storage temps from –55 to +105 °C (-67 to 221 F). Additional environmental specifications for the 9905-895 are:
- Humidity …... 95% at 38 °C
- Mechanical shock …... US MIL-STD 810C, Method 516.2, Procedures I, II, V
- Electromagnetic susceptibility …... ANSI/IEEE C37.90.2; ANSI C37.90.1-1989
- Vibration …... US MIL-STD 167, Type I
The 9907-007 offers either phase matching or slip frequency synchronizing. Actual slip frequency and breaker delay values are used to anticipate a minimum phase difference between generator and bus at actual breaker closure for both methods. There is an automatic dead-bus closure function on this control, where only one DSLC control is granted dead-bus closing permission through locking techniques over the communications network.
Additional synchronizer features that may be enabled or disabled during setup include time delayed automatic multi-shot reclosing, voltage matching, auto-resynchronizing, and synchronizer timeout alarm
For additional information, product specifications, and safety precautions for Woodward part 9907-007 DSLC, please consult the Woodward DSLC Digital Synchronizer and Load Control Manual 02007, available online.