647 Chair Tilt Up / Down Function Troubleshooting
This illustration shows only the components that affect the Tilt Up / Down function. A detailed description of Tilt Up / Down operation appears below.
•If power light is OFF: Refer to: Power to the Chair for troubleshooting.
•If power light is ON: Proper voltage is present at PC board.
Is there power to the chair?
When voltage is present at the PC board, the power light is illuminated. Refer to: Power to the Chair for description of current flow to the PC board.
Power to Foot Control / Touch Pads
Circuitry on the PC board supplies 8-10 VAC to the foot control and touch pads.
Tilt Up Operation
When the Tilt Up function is activated, current flows thru the foot control / touch pad to the main PC board. Circuitry on the main PC board supplies approximately 48 VDC to the tilt actuator motor.
The actuator motor runs and raises the seat section.
The main PC board continuously monitors the tilt position sensor.
When the tilt position sensor detects that the seat section has reached its upper limit, or that the chair is in a potential crash position, the Tilt Up function will not operate*.
Actuator motor runs until
1.Foot control / touch pad button is released.
2.Crash Avoidance System activated*.
3.Emergency Stop button is pressed.
4.Position sensor detects upper limit.
5.Overcurrent protection tripped
6.Software timeout is reached, 30 seconds.
Tilt Down Operation
When the Tilt Down function is activated, current flows thru the foot control / touch pad to the main PC board. Circuitry on the main PC board supplies approximately 48 VDC to the tilt actuator motor.
The actuator motor runs and lowers the seat section back to a flat position.
The main PC board continuously monitors the tilt down limit switch and the tilt position sensor.
If the tilt down limit switch is tripped, open, the tilt Down function will not operate.
If the tilt position sensor detects that the chair is in a potential crash position, or that the seat section has reached its lower limit, the Tilt Down function will not operate.
Actuator motor runs until
1.Foot control / touch pad button is released.
2.Tilt Down limit switch is tripped.
3.Crash Avoidance System activated*.
4.Emergency Stop button is pressed.
5.Position sensor detects lower limit.
6.Overcurrent protection tripped
7.Software timeout is reached, 30 seconds.
*Refer to: Crash Avoidance System for a detailed description of crash position, and the functions that are disabled.
