molbox™ RFM™ OPERATION AND MAINTENANCE MANUAL
© 1998-2007 DH Instruments, a Fluke Company
Page 48
1. High Isolation:
Closed
2. Low Isolation:
Closed
3. Bypass:
Closed
4. Mirorange Bypass: Closed if
Active
Open
if
Bypassed
Figure 8.
molbox RFM
Internal Pneumatic Schematic – LEAK CHECK molbox
Once the molbox RFM pressure connections are vented, press
[ENTER]
.
1.
The pressure read by the upstream RPT (left),
the downstream RPT (right) and the pressure
unit of measure (middle).
2.
The ratio of the upstream RPT reading to the
downstream RPT reading.
3.
Leak check count down in seconds.
347.466 kPaa 35.459
1.03579:1 WAIT: 60
molbox RFM counts down for 60 seconds while monitoring the ratio of the two
pressures and then determines whether an internal leak was present.
A significant leak in a pressure isolation valve or a bypass valve between the two
channels will cause the ratio between the two pressures to vary.
The molbox RFM LEAK CHECK function
should end with the prompt:
molbox passed the
leak check
If any other prompt is present, repeat the process. If the molbox RFM is
equipped with the microrange option, run the leak test with the microrange in the
opposite condition (active or bypassed). If the leak check fails consistently, note
the failure message and contact a
DHI
Authorized Service Provider.
