DH Instruments PPC4, Руководство по эксплуатации и обслуживанию

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PPC4™ OPERATION AND MAINTENANCE MANUAL
© 2009 DH Instruments, a Fluke Company Page 66
4.4.4 <Setup>, <UL> (Upper Limit)

PURPOSE
To set the upper and lower limit pressure value for a pressure range and measurement mode (see
Section 3.2.21).

OPERATION
To view or edit upper and lower limits use <Setup> , <UL> .
If the current measurement mode is absolute or gauge, there is an upper limit only.
The display is:
1. Entry field for upper limit value in active pressure unit of
measure and measurement mode.
Upper limit: IH
204.000 kPa a
Edit the upper limit value as desired. The maximum upper limit is 105 % of AutoRange range
or 102 % of default Q-RPT range, whichever is smaller.

to return to the Main Run Screen
with the new upper limit active.

to return to the Main Run Screen with no change to the
upper limit.
If the current measurement mode is negative gauge or the Q-RPT is a BA100K, there is also a
lower limit. The display is:
1. Entry field for upper limit value.
2. Entry field for lower limit value and active range pressure unit
of measure and measurement mode indication.
Upper:104.00 IH
Lower:-110.00 kPa g
Edit the upper and lower limit values as desired. Use the cursor control keys to move
between the two edit fields. The lower limit must be a negative value.

to return to the
Main Run Screen with the new upper and/or lower limit active.

to return to the Main Run
Screen with no change to the limits.
When the upper or lower limit has been exceeded, the display of current pressure flashes and
a buzzer sounds for 3 seconds at 2 second intervals. Reduce pressure using direct pressure
control keys or an automated pressure command to return to normal operation.
Note
Upper limit values are specific to each range and measurement mode. Be
careful not to assume that the upper limit set in one measurement mode
will apply to the other.
For example, if you set 150 kPa as the upper limit in gauge mode, the upper
limit will not be 150 kPa in negative gauge mode of the same range.
4.4.4.1 Over Pressure Function
In addition to the UL function, PPC4 has an over pressure function (see Section
3.2.21.1).
To recover from an overpressure condition, correct the overpressure condition
and cycle PPC4 power. Be sure to correct the condition that caused the
overpressure before cycling power.