DH Instruments PPCK PLUS, Руководство по эксплуатации и обслуживанию

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PPCK+™ Operation and Maintenance Manual
©2001 DH Instruments, Inc .
Page 12
Minimizing the length and complexity of the test connection tubing enhances control
performance and reduces pressure setting time. For optimum operation, the total volume of
the device or system under test including connecting tubing should be less than 500 cc
(30 in
3
) up to 200 MPa (3 000 psi) and less than 200 cc (12 in
3
) over 200 MPa (3 000 psi).
PPCK+ pressure control will not operate properly if there are excessive leaks in the
test system. As a general rule, the maximum acceptable leak rate for optimal PPCK+
automated pressure control operation and to assure in tolerance measurements with default
pressure control parameters is ± 0.01 % of active range FS/second. If working with larger
leaks is unavoidable, consider using STATIC CONTROL mode (see Section 3.1.2.4).
2.3.6 CONNECTING THE DRIVE PRESSURE SUPPLY (DRIVE IN PORT)
PPCK+’s high pressure valves are actuated by a drive pressure. This drive pressure must be
connected and properly set for PPCK+ to operate properly.
Using a pressure connecting hose of appropriate pressure rating, connect the drive pressure
supply to the DRIVE IN connection on the rear panel of PPCK+. The DRIVE IN connection is
1/8 in. NPT F .
The drive pressure must be between 700 - 850 kPa (100 - 120 psi) . The supply pressure
must be stable
±
5 % for PPCK+ pressure control to operate within specifications (see
Section 1.2.3).
Never connect a pressure supply to the DRIVE IN port that is greater than 1 MPa (150 psi).
Damage to PPCK+ could result.
2.3.7 DRIVE OUT PORT
The DRIVE OUT port is the exhaust point for drive air used by PPCK+’s high pressure valve
drive system (see Figure 5). The DRIVE OUT port should be open to atmosphere and
unobstructed to allow drive air to escape. The drive air consumption is very low so there is
no significant flow through the DRIVE OUT port.
Though a pressure hose can be connected to the DRIVE OUT port to direct the exhausted
gas flow, the flow is very low and a completely unobstructed connection to atmosphere must
be maintained.
The PPCK+ DRIVE OUT port is 1/8 in. NPT female .
NEVER plug, obstruct or connect a supply pressure to the DRIVE OUT port.