Siemens 7MF4233 series

On-Line Operation UMSITRPDS3-1
November 2005
6-14
6.2.8 Pushbutton and Function Disable
Mode 10 is used to disable some or all magnetic pushbutton functions. In addition, a write protect
function can be activated to prevent changing of saved parameters. There are five options as shown in
Table 6.3.
TABLE 6-3 Pushbutton and Function Disable Options
Symbol Explanation
no symbol No disable.
LA Input pushbuttons disabled. Operation via HART is enabled.
LO Zero can be set; all other functions are disabled. Operation via HART is enabled.
LS Only zero and full scale can be set (see Section 6.3); all other functions are disabled.
Operation via HART is enabled.
L Write protect enabled. Operation by HART disabled.
LL is another pushbutton disable that is available in HART; see Section 6.4.9. The disable option symbol
will appear in the lower left quadrant of the digital display. To cancel a disable option, see Section 6.2.1.
To select a pushbutton or function disable option:
1. If LO or LS is to be selected, first press the M pushbutton to go to mode 13. Select either Current in
mA or Current in %. Otherwise, a change in the output variable will not be detected when an arrow
pushbutton is pressed.
2. Press the M pushbutton to go the mode 10. Select a disable option by pressing either arrow
pushbutton.
3. Press the M pushbutton to save the selection.
Note
When a transmitter is delivered without a display, disable option LS is active. If
the transmitter is to be permanently operated without a display, be sure option LS
remains active.
6.2.9 Flow Measurement (Differential Pressure only)
Select the characteristic of the output current as follows:
• Linear - proportional to the differential pressure
• Square Root - proportional to the flow
Below the square root function’s switch point the output current can have a linear characteristic or be
switched off. See Figure 6-2.
To select the characteristics:
1. Press the M pushbutton to enable mode 11.
2. Press either arrow pushbutton to select the desired characteristic.
3. Press the M pushbutton to save the selection.
4. Press the M pushbutton to enable mode 12.
5. Press either arrow pushbutton to select an switch point between 5 and 15%.