Instruction Manual

16
6.6 Checking the Diagnostic Window
Bypass Port PTP Port
Connected to The hydraulic bypass valve on
the side of the pump head
The PTP push-button valve on
the top of the pump head
Function Bypass protects the pump from
excessive pressure and hydraulic
upset conditions
Allows any air trapped in the
hydraulic system to escape
Normal operation No oil should move through this
port when the pump is operating
normally
Small amount of oil will weep
from port during operation,
flow increases if PTP button is
depressed
Abnormal operation Oil is seen flowing from the port No oil moving through the port
at any time, or product (not oil)
is seen
Things to check if
abnormal operation is
suspected
o Discharge pressure too high
o Bypass valve setpoint too low
o Bypass valve malfunction
o Other upset condition
o PTP damaged
o HPV filter screen clogged
o HPV not operating properly
o Diaphragm damaged
PTP port
(center)
Bypass port
(side)