DH Instruments MFC SWITCHBOX, User Manual

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3. OPERATION
Page 7 © 1997-2008 DH Instruments, a Fluke Company
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3.1 OVERVIEW
The MFC Switchbox in and of itself does not require any special setup or configuration. It just needs to
be connected to the molbox1 or MFC-CB and DUTs as described above, plugged in and powered on by
actuating the power switch on the MFC Switchbox rear panel.
3.2 GENERAL OPERATION
Before using the MFC Switchbox the MFC profiles for the connected DUTs must be defined in the
molbox1 or MFC-CB. This is accomplished using the setup function to define the MFC profile. For
details on the MFC profile definition, see the molbox1 or MFC-CB Operation and Maintenance Manual.
In order to support MFM calibrations using the MFC Switchbox the device type is specified to the MFC
profile. After entering the MFC range, you will be prompted to enter the device type. The device type for
any voltage based profile can be either ‘measure’ or ‘control’. If the profile indicates measure, then
channel one will be used for control whenever the channel is selected that is associated with this profile.
If the profile indicates control, then the selected channel will be used for both measurement and control.
When calibrating MFMs, the range of the MFC setup for channel 1 must be wide enough to cover the
range of all the MFMs being calibrated on the other channels.
For details on configuring the MFC channels and profiles see the molbox1 or MFC-CB Operation and
Maintenance Manual. Once the MFC channels have been configured using the setup menu, the MFC
channel can be selected by pressing the MFC function key on the molbox1 or MFC-CB front panel.
When the MFC function key is first pressed the screen prompts the
operator to select the MFC channel (
<0> disables).
The MFC Switchbox must be connected to the molbox1 or MFC-CB at the time of this selection, but does
not have to be connected during the MFC setup described above. Entering
<1> , <2> , <3> , <4> or <5>
selects the corresponding channel on the MFC Switchbox and enables the MFC function. When not
using the MFC Switchbox, select Channel #1 when activating the MFC function.
The operator is then prompted to select the MFC profile. The profile number
that is associated with the selected channel is automatically displayed. This
screen allows the operator to override the profile selection made during setup.
The number refers to the profile number. When the profile number desired is entered a summary of the
profile is displayed. When
[ENTER] is pressed again, the display returns to the main run screen and the
MFC function is active using the MFC profile selected. The MFC Switchbox must be connected
to the molbox1 prior to pressing
[ENTER] or the message that actually triggers the switching inside the
MFC Switchbox will be missed. With molbox1, the text <MFCn> or <MFMn> (where n is the channel
number and the type depends on the channel configuration) will be displayed in the bottom right hand
corner of the main run screen. With MFC-CB, the text
<Dn,c> (where n is the number of the active
MFC-CB channel and c is the number of the active MFC Switchbox channel.
When the MFC function is active, pressing [ENTER] from the main run screen or an MFC run screen
allows entry and execution of the MFC setpoint command.