Metrohm 709 IC Pump - Manual (Page 31)

3.6 On/off switching of the external control
709 IC Pump
23
3.6 On/off switching of the external control
Switching on Pressing the <EXT.> key 8 switches on the external
control. The interface (RS232, see section 5.1 or "Cur-
rent Loop", details on request) is selected with sliding
switch 36. With active external control the LED 7 above
the <EXT.> key 8 lights up. All keys with the exception
of <SELECT> 4 (selection of display function) are
blocked.
Switching off To switch off the external control, the <EXT.> key 8 is
pressed again. The LED 7 goes out and all functions
are once more accessible manually via the keypad.
3.7 Inquiry of the current pressure
The current pressure of the pump can be queried at any time when the
pump drive is switched on. Proceed as follows:
1 Select "P
actual
"
Press <SELECT> key 4 until the "P
actual
" LED 13 lights up.
2 Read pressure
The current pressure (in MPa) is shown in display 1.
3.8 Overview of the key functions
R/S
On/off switching of the pump drive
When the pump drive is switched on, the LED above
the key is on.
SELECT
Selecting the display function
FLOW Current flow rate in mL/min
Range: 0.01...5.00 mL/min
P
min
Minimum shutoff pressure for automatic
shutdown of the pump drive
Range: 0.1... 50 MPa (1...500 bar)
(P
min
< P
max
)
0.0: no shutoff