™/S, MOLBLOC TERMINAL OPERATION AND MAINTENANCE MANUAL
© 1995 - 2010 Fluke Corporation, DH Instruments Division
Page 106
Note
The RS232 test can fail for three reasons:
1. The RS232 cable being used is incorrect (see Section
4.2.1.1 for information on the correct cable).
2. COM1 and COM2 do NOT have the same serial
communications settings and therefore cannot
communicate together (see Section 3.6.6.1 to set the
COM ports).
3. COM1 or COM2 is defective.
The reason for failed communications is almost always a cable
or incorrect RS232 interface settings. Be sure that these are
correct before concluding that a COM port is defective.
3.6.7
<7Drivers>
PURPOSE
To control the output signals of ’s 8 channel, 12 V external drivers.
Note
The <3drivers> function is an optional feature of . If this option
was not ordered with the , the driver hardware has not been
installed and the operation of <3drivers> will have no effect.
PRINCIPLE
external drivers are available to drive peripheral equipment in a system
(e.g., manifolding valves for selecting gas supply to the molbloc or automatically directing
flow to molbloc channel A or B). The driver electrical connections are available from a rear
panel connector (see Section 7.2 for driver specifications and pin outs).
OPERATION
To access the driver control function, press
[SPECIAL]
and select
<7drivers>
.
The display is:
External Drivers: 1
2 3 4 5 6 7 8
Pressing the keypad numerical key driver number turns that driver ON and OFF with either a
momentary or a toggled response. An active driver is indicated by
<*>
immediately following
the driver number. Pressing
[ENTER]
while in the External Drivers menu causes a menu to
appear that allows selection of whether the driver actuation by selecting the driver number
will be
<1momentary>
or
<2toggle>.
3.6.8
<8Head>
PURPOSE
To cause a pressure fluid head correction to be added or subtracted to the pressure
measured by the reference pressure transducers in order to predict the pressure at
height the height of the molbloc when the molbloc is at a level other than the ’s
reference level.
PRINCIPLE
measures absolute and differential pressure in molbloc flow elements. The
reference pressure transducers (RPTs) are calibrated with the height of the rear
panel pressure quick connectors as the pressure reference level. Sometimes, when
performing a calibration or test, the molbloc is at a different height than the ’s
pressure reference level. This difference in height, frequently called
head
, can cause a
