Product Description

This Woodward-manufactured overspeed protection device samples prime mover speed every 5 ms to monitor for overspeed conditions. If conditions are met, a trip relay is activated. Total response time is kept at or below 40 ms. Model 9905-886 is a 220 Vac (Units A, B, and C each have their own power supply), energize-to-trip version. Because this is an energize-to-trip model, interposing relays will not actuate if the input power is lost.

This model has an accuracy rating of 0.1% when operating at 25 °C, though it can handle an operating temperature range of –25 to +65 °C (–13 to +149 °F). ProTech 203 model 9905-886 must be installed in a location that provides adequate ventilation for cooling the hardware. This device also requires protection from direct sunlight, moisture, vibration, and devices that may cause electromagnetic interference.

Woodward ProTech 203 Overspeed Protection System Manual 85191 (version B) should be reviewed before installing model 9905-886.

This system uses three individual speed-sensing units to monitor prime mover speed. All three of these units are kept in the same enclosure, which meets NEMA 4X standards when the optional stainless steel hubs are used.

Model 9905-886 has LED indicators and alarm outputs (separate sets for each unit) to alert of errors, such as:

• Loss of MPU signal
• Tripped unit
• CPU failure