Epson Stylus Pro 5000 Service Manual page 50

Stylus Pro 5000
If the output of the +42 V line exceeds +48 V, the over voltage protection
circuit shuts down the C228 PSB board. The line is monitored by Zener
diodes ZD51 and ZD81 through ZD86.
*3) +28 VDC Line Over Voltage Protection Circuit
This circuit is on the same line as the +42 V line over voltage protection
circuit. It shuts down the C228 PSB board when the +28 V line output
exceeds +33 V.
*4) Delay Circuit
If the power is turned off at the control panel, the delay circuit provides
power for the power off sequence. During this sequence, the printer:

Closes the ink valve
Locks the carriage into the home position



Caps the printheads
Ejects any paper still in the paper path



Resets the ASF if it's in use
Chapter 2 Operating Principles
2-18