HYDAC International FPU Notice D'utilisation page 45

5. For use on the accumulator
5.1. Preparation
NOTICE
Adapter A3 must only be used with the
FPU-1.
Adapter A3H must only be used with the
FPU-2.
– On bladder accumulators, unscrew valve
protection cap (S) and seal cap (H) and
remove O-ring (O). Slightly unscrew the
adjusting screw of adapter A3/A3H and
screw adapter A3/A3H onto the accumulator
gas valve.
– On piston and diaphragm accumulators
FPU-1:
Loosen the int. hex. screw (P) with an Allen
key SW6, DIN ISO 2936 by approx. 1/2 a
turn.
FPU-2:
Loosen the int. hex. screw (P) with the
spindle (A).
– Manually screw FPU connector (D) onto
adapter A3/A3H on the bladder accumulator
or onto the accumulator gas valve of the
piston and diaphragm accumulators.
– Rotate charging device so that the pressure
gauge is in a good position for taking
readings.
5.2. Testing
– Firmly close the release valve (B) on the
FPU.
– On bladder accumulators, open the gas
valve insert (E) in the hydraulic accumulator
by rotating the spindle (A) clockwise.
– On piston and diaphragm accumulators,
open the int. hex. screw (P) in the hydraulic
accumulator by rotating the spindle (A)
anti-clockwise.
– Rotate spindle (A) until the needle of the
gauge starts to move.
– The pressure gauge now displays the
pre-charge pressure in the hydraulic
accumulator.
FPU-1:
The check valve (C) prevents the nitrogen
from escaping.
FPU-2:
See section "Safety information".
5.3. Reducing the pre-charge
pressure
– The release valve (B) is opened slowly.
The nitrogen is released into the
atmosphere.
5.4. Increasing the pre-charge
pressure, but no initial
charging
Procedure when using the FPU-1
– Connect the flexible charging hose to the
shut-off valve of the nitrogen bottle, the
pressure reducer (if present) or the gas
safety valve (if present) using connector G1
(GM1, GW1). For nitrogen bottles from other
countries, use a G adapter (see fold-out
page, drawing 5 I).
– Connect the cap nut (M) of the charging
hose to the check valve (C) of the FPU-1.
– Close the pressure reducer (if present).
– CAUTION WHEN OPENING the shut-off
valve on the nitrogen bottle and SLOWLY
ADJUST the pre-charge pressure at the
pressure reducer (if present) so that the gas
valve insert (E) in the hydraulic accumulator
is not damaged.
– Interrupt the charging process from time to
time and check the pre-charge pressure
reached.
– Repeat this process until the required
pre-charge pressure is reached. After
temperature equalization has taken place,
re-check the pre-charge pressure and adjust
if necessary. If the pre-charge pressure is too
high, it can be reduced using the FPU-1
release valve (B).
GB
45