DH Instruments PPC4, Руководство по эксплуатации и обслуживанию

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PPC4™ OPERATION AND MAINTENANCE MANUAL
© 2009 DH Instruments, a Fluke Company Page 118
5.7.8 Control
5.7.8.1 Pressure Limits

PURPOSE
To set the upper and lower limit pressure value for a pressure range and
measurement mode (see Section 3.2.21).

OPERATION
[Settings], <Control>, Pressure Limits opens the screen to edit or reset the
Upper and Lower Limits.
To modify the upper limit, edit the value, noting the pressure units associated with
this value.
[OK] to accept changes and return to the Main Run Screen. [Back] to
return to <Control> and make no changes. [Esc] or

to exit to the Main Run
Screen and make no changes.
Note
•
If the current measurement mode is absolute or gauge,
there is an upper limit only. The maximum upper limit is
105 % of AutoRange range or 102 % of default Q-RPT
range, whichever is smaller.
•
RPM4 with Q-RPT full scale spans below 14 MPa have SDS
self defense system to isolate and protect the Q-RPTs. If
an external RPM4 SDS pressure rating is less than the
PPC4 maximum pressure then a warning will be displayed
on the PPC4 front panel when the RPM4 is detected. In
addition, AutoRanged ranges greater than the SDS rating
are not allowed (see Sections 3.2.5, 6.5.4, 3.2.8). In order
to create AutoRanged ranges or generate pressures above
the SDS pressure rating the RPM4 must be disconnected
or the RPM4 SDS must be upgraded to a higher pressure
rating. Upgrades may be done at the DH Instruments
service center (see Table 36).
If the current measurement mode is negative gauge or the Q-RPT is a BA100K, there
is also a lower limit that may be edited. For an Axxx Q-RPT operating in negative
gauge mode, the lower limit is –ATM by default. The value may be edited but must be
negative. To restore the value of –ATM use
[Default Limits] .
Note
•
The lower limit must be a negative value.
•
The default lower limit for a BGxxx Q-RPT in negative gauge
mode is the negative equivalent of the upper limit
•
The default lower limit for a BA100K Q-RPT in negative gauge
mode is 66 kPa (9.6 psi).
[Default Limits] resets the Upper and Lower Limits to the default values for the
active Q-RPT and range.
[OK] to accept the changes and return to the Main Run Screen. [Back] to return
to <Control> without making changes. [Esc] or

to exit to the Main Run
Screen without making changes.