9907-347

About the 9907-347

If you’re looking for a de-energize-to-trip overspeed protection system, the Woodward ProTech 203 series of overspeed protection devices have many available options for compatibility with a wide range of power supply combinations. This device, ProTech model 9907-347, is one of 24 Vdc versions. Each speed-sensing unit in this system has a separate power supply.

Because this is a de-energize-to-trip system, voter relays are actuated if there is a loss of power to this ProTech 203 overspeed protection system. Two voter relays are actuated by each speed-sensing unit. These units are in an enclosure that is NEMA 4 and 4X certified (North America) and IP54 rated (Europe).

Model 9907-347 may require the use of double-shielded wire or other precautions if it is installed near devices that produce electromagnetic interference, such as high-voltage or high-current devices. Additional information on this and other precautions is in Woodward ProTech 203 Overspeed Protection System Manual 85206.

On the front panel of the enclosure are three operator interfaces, one for each unit. The two-line LCD displays the 9907-347 tunable parameters, such as Trip Speed Set Point and MPU Failed Timeout. Present Speed is the first displayed, the rest are cycled through using the touchpad below the screen.

In the event of an error or any event requiring attention, the LCD will display an error code. Certain situations, such as an MPU failure or CPU failure, will trigger an LED indicator to illuminate. There is also an alarm output to indicate a tripped unit.