Watson-Marlow 620U - Manual (Page 28)

Watson-Marlow 620UN, 620U, 620SN, 620S User Manual 28
14.3 Speed
To change the running speed:
Use the UP and DOWN keys to change the pump’s running speed within limits
of the minimum allowed speed and the maximum allowed speed. The minimum
speed possible is 0.1rpm.
Note: You can reduce the pump speed from 0.1 rpm to 0 rpm by a further
press on the DOWN key. The pump is still in the running state and the rotation
symbol will continue to move. Press the UP key to return the pump to the min-
imum speed.
Note: The maximum allowed speed of the drive defaults to 165rpm. It is possible
to set this limit at any speed up to 265rpm. See 16.7 Set maximum allowed speed,
and section 3 Five-year warranty.
14.4 Direction
To toggle the pump’s rotation sense:
Press DIRECTION to toggle the pump between clockwise and counter-clock-
wise rotation.
Note: Direction control is available subject to access not being limited by security
code. See 16.15 Security code.
14.5 Keypad lock
The keypad can be locked to prevent changes to pump speed or other settings, and
make it possible only to start or stop the pump. The padlock symbol shows on the
display.
While the pump is running, hold down the START key for two seconds. The
padlock symbol shows and only the START and STOP keys function.
The keypad may also be locked while the pump is stopped. Hold down the
STOP key for two seconds. The padlock symbol shows and only the START
and STOP keys function.
To unlock the keypad while the pump is running hold down the START key for
two seconds. The padlock symbol is removed. If the pump is stopped hold
down the STOP key until the padlock symbol is removed.
Note: Keypad lock is available subject to access not being limited by security
code. See 16.15 Security code.
14.6 Keypad beep
The pump keypad can operate silently or indicate a positive key-press with a beep
sound.
To toggle the sound on and off, stop the pump. Turn off the mains power switch
at the rear of the pump.
Depress the UP and DIRECTION keys while switching on the mains power
switch at the rear of the pump.
UN, U, SN, S