Fluke RPM4-AD, Руководство по эксплуатации и обслуживанию

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3. OPERATION
Page 55 © 2005-2007 DH Instruments, a Fluke Company
3.4.4 <4UL> (UPPER LIMIT)
 PURPOSE
To set the upper and lower pressure limit values for a pressure range and measurement mode.
 PRINCIPLE
The UPPER LIMIT function provides the user with settable pressure limits at which an alarm
sounds. Absolute and gauge measurement modes (see Section 3.3.3,

PRINCIPLE) have
upper limits only. Differential and negative gauge modes have a lower limit.
When the limit is reached, RPM4’s beeper sounds intermittently as long as pressure is
outside the limit.
The UPPER LIMIT function has two purposes. First, when UL is set to its default value, it serves
as a warning that the maximum pressure of the active Q-RPT is about to be exceeded. Second,
UL can be set by the user to a value other than the default value to provide an alarm that a
specific pressure limit has been exceeded. This feature is often used to help protect an external
device or system on which RPM4-AD is being used to measure pressure. For example, it might
be set just over the full scale of a device under test (DUT) that is being calibrated.
The default upper limit is 102 % of Q-RPT maximum working pressure. The default lower
limit (negative gauge mode only ) is – 110 kPa (- 16 psi).
In differential measurement mode (see Section 3.2.6), UL has upper and lower limits. If
the measurement unit is an airspeed unit, there is no lower limit.
In differential measurement mode, the ULs on the Lo Q-RPT and Hi Q-RPT default range are
also active so that line pressure (Lo Q-RPT) and total pressure (Hi Q-RPT) upper limit can be
set and monitored in addition to a differential limit.
 OPERATION
To view or edit upper and lower limits press [SETUP] , <4UL> .
If the current measurement mode is absolute or gauge or if the active unit of measure is an
airspeed unit, 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: Hi
163.2 kPa a
Edit the upper limit value as desired. The maximum upper limit is 102 % of default Q-RPT full
scale. Press
[ENT] to return to the MAIN RUN screen with the new upper limit active. Press
[ESC] to return to the MAIN RUN screen with no change to the upper limit.
If the current measurement mode is negative gauge or differential and the unit of measure is
not an airspeed unit, there is an upper limit and 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: 63.2 Hi
Lower:-110.0 kPa g