SEAL 1987825 - Caterpillar

Due to typical noise levels in engine environments, hearing protection should be worn when working on or around the RAPTOR valve.
The RAPTOR valve is typically continuously connected to the supply voltage. When the key switch input is connected to a high signal (supply [+]), the RAPTOR valve will switch its internal supply voltage on. The processor then performs a diagnostic check. If there are no problems detected, the valve will read the CAN ID input pins and begin sending diagnostic information on the CAN link. The RAPTOR valve will annunciate the CAN ID code by displaying one, two, three or four red flashes on the diagnostic LED.The actuator is powered and positions the valve at its minimum position. If there is a problem detected with positioning the valve, the valve will be closed against the minimum mechanical stop, if possible. Next, the RAPTOR valve checks for flow parameters (Specify Gravity, K factor, and Max PWM values) in non-volatile memory. If these values are not available, the value will remain at minimum position and will send diagnostic messages until these values are received by CAN communication.If the Specific Gravity, K and Max PWM values are available, the RAPTOR valve will look for a Qgn (mass flow demand signal) on the CAN bus. If this signal is not received, it will switch to the PWM secondary (backup) mass flow demand signal. If neither signal is available the RAPTOR valve will set the flow demand to zero internally.