3. OPERATION
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© 2005-2007 DH Instruments, a Fluke Company
OPERATION
To access the HEAD function, press
[HEAD]
. The display is:
1.
Edit field for head height.
2.
Test gas currently specified for the head correction.
Edit head height:
+ 25 cm N2
Edit the head height to the desired value. Press
[ENT]
to return to the MAIN RUN screen
with the new head correction active. Press
[ESC]
to return with no changes.
The reference height of the RPM4-AD
pressure measurement is the middle of
the RPM4-AD TEST ports. The head
height should be entered as a positive
value if the device or system under test
is higher than the RPM4-AD and
negative if it is lower.
The HEAD function is NOT Q-RPT specific. The HEAD ON or OFF status and settings
remain the same as active Q-RPT is changed.
When a head correction is being applied, it is indicated by <h> in the top line of the MAIN
RUN screen (see Section 3.1.1). When the head correction is zero, the <h> is not shown.
To change units of head height between inches and centimeters and to change the test
gas species, use [SPECIAL], <3head> (see Section 3.5.3).
3.3.8
[SDS] (SELF DEFENSE SYSTEM)
PURPOSE
To CLOSE SDS on all reference pressure transducers (Q-RPTs). To OPEN SDS on the
active Q-RPT/
TEST
port.
The [SDS] key should be used with care to avoid accidentally over pressuring a Q-RPT.
Always double check to ensure that the pressure applied to the Q-RPT’s TEST port is
lower than the Q-RPT’s maximum pressure before OPENING SDS.
SDS can be set to permanently be OPEN as if no SDS were installed (see Section 3.5.4.2).
PRINCIPLE
SDS is a self defense system to protect RPM4-AD Q-RPTs from overpressure. SDS
CLOSES automatically to protect a Q-RPT that is not active. Activating an individual Q-RPT
automatically CLOSES SDS on the other Q-RPT. Powering down the RPM4-AD or
energizing it also CLOSES SDS on all Q-RPTs.
