Overview
• Drive
The rotary knob (B, see Fig. 1) of the Wireless Controller (WiCo) allows the speed of the stirrer to be adjusted over the
entire speed range.
• Motor protection
The stirring instrument is suitable for continuous operation. The motor current is limited electronically. The instrument has
an anti-stall and anti-overload system.
If a fault occurs, a safety circuit immediately switches off the motor permanently through a relay in the power board. A
fault occurs if the safe functioning of the instrument is compromised.
• Speed – normal operation
Speed - regulated (no variation in speed)
The speed is monitored and regulated by processor controlled. The target speed is constantly compared with the actual
rotation speed value of the output shaft and variations corrected. This guarantees a constant speed even if the viscosity
of the substance being stirred changes.
Fluctuations in mains voltage within the permitted tolerance range have no effect on the quality of regulation and constancy
of speed.
The speed is set using the front knob (B, see Fig. 1). During normal operations the speed value on the display (C, see Fig. 1)
corresponds to the speed of the output shaft in revolutions per minute (rpm).
• Speed – overload operation
In order to overcome peaks in the load such as arise when a solid or viscous medium is added, the stirrer can be run for
a brief period at twice its rated power. When running in the overload range (for instance if the viscosity has increased at
a particular stage of the process) the speed will be reduced to a degree sufficient to keep the torque on the stirrer shaft
within the rated torque of the device.
The speed is continually adjusted whilst the stirrer is running to correspond to the operating conditions and so that it
matches the set speed as closely as possible.
Overload status 1:
The device is already running within the overload range, whereby the actual speed does not match the set speed. This
condition is maintained as long as neither the motor current nor the temperature exceeds their permissible limit value.
This is indicated by the torque value flashing in the display.
Once the load reduces to a value within the normal range again, the torque value ceases to flash.
Overload status 2:
If the device is subjected to a fluctuating load which causes the torque to be more than double the normal torque, the
actual speed of the stirrer shaft is quickly reduced to zero.
Message in the display: Error 4 (see "Error codes" section).
• Output shaft
The clamping chuck and output shaft permit clamping VWR
output shaft is designed as a hollow shaft and the opening on the top side of the housing is closed with a plastic cover.
When the stirrer cover is opened, it is possible for stirring shaft to be pushed out over the top edge of the housing at
standstill, e.g. during changing container.
For safety reason, the stirrer cover must be pushed back into the opening of the housing so that it is properly closed. This
is the only way to ensure that working with the unit is safe and that media cannot enter the instrument.
Please see section "Safety instructions"!
DANGER
• Speed display
The speed is set using the rotary knob (B, see Fig.1) on the front of the Wireless Controller (WiCo).
The speed is displayed directly in revolutions per minute (rpm) in the display (C, see Fig.1) of the Wireless Controller.
recommend stirrer tools (see section "Accessories"). The
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