About the 9905-711
Manufactured by Woodward, part number 9905-711 is a microprocessor based DSLC Digital Synchronizer and Load Control unit. This model does not have power factor control or process control functions, as it is a reduced upgrade level DSLC part number. It is intended for applications which do not require integrated power factor or process control.
Model number 9905-711 is designed for paralleling, synchronizing, loading, and unloading of three-phase generator sets when used with a Woodward speed control and an automatic voltage regulator (or other compatible device). Built in diagnostics; automatic generator loading and unloading; setup, metering, and diagnostic capability through a handheld programmer terminal; droop, base load, and isochronous load control capability; and reverse power relay are just a few of the available functions.
9905-711 has a 120/240 voltage input and a speed bias of 1-5 Vdc. This WYE PT Configuration unit is rated for 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 9905-711 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 9905-711 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
- Synchronizer timeout alarm
Precautions to protect against static damage should be followed when working with or near the 9905-711. Please consult Woodward DSLC Digital Synchronizer and Load Control Manual 02007, available online, for additional information, product specifications, and safety precautions for Woodward part 9905-711 DSLC. Repairs of part 9905-711 are available through AX Control.
