DLab OS20-Pro User manual

Overhead Stirrers
OS20-S/Pro
OS40-S/Pro
VERSION20170204

CONTENTS
Chapter 1: Working Principle ......................................................................................................... 1
1.1 Introduction ........................................................................................................................ 1
1.2 Structure.............................................................................................................................. 2
Chapter 2: Removal and Installation of Instrument ....................................................................... 3
2.1 Removal......................................................................................................................... 3
2.2 Main parts illustration ................................................................................................... 5
2.3 Circuit Connections (OS20-Pro&OS40-Pro) ................................................................... 6
2.4 Replacement of drive board.......................................................................................... 7
2.5 Replacement of Control Modules ................................................................................. 7
2.6 Replacement of Movement .......................................................................................... 8
2.7 Replacement of Photosensor ........................................................................................ 8
Chapter 3: trouble shooting ........................................................................................................... 9
Chapter 4: Test method ..................................................................................................................... 9
4.1 Check photosensor Module .......................................................................................... 9

1
Chapter 1: Working Principle
1.1 Introduction
FIG.1
You can mix the sample in container by using Overhead Stirrer with stirring impeller blades. The
high viscosity samples can be mixed by using strong stirring force.
Fig. 1 is the schematic diagram of OS40 (20)-Pro Digital Overhead Stirrer. On control panel of the
instrument, there are LCD display, mode button, speed control knob, speed/torque indicator,
power/overload protection indicator, and power switch. And on the back of instrument, there are
RS232 interface and power outlets. After properly connect the power cord and turn on power
switch, you can set experimental conditions on the control panel by speed control knob, real-time
observe setting values and actual values of parameters on LCD screen.
Stirring impeller is optional. Now, four models are available, and they can mix different
concentrations of the samples as tools of OS40 (20)-Pro.
For the control panel settings and functions of various types of Overhead Stirrers,
speed
control
knob
LCD
display
LED
display
RS232
Interface
OS20-Pro Type Ⅰ
√ √
OS40-Pro Type Ⅰ
√ √
OS20-S Type Ⅱ √
OS40-S Type Ⅱ √
LCD Display
Drill chuck
Mode Button
Speed Control Knob
Speed/Torque Indicator
Power/Over load Indicator
Power Switch

2
Type Ⅰ Knob: The knob of Digital Overhead Stirrer can be rotated and pressed. There is no stop
point when it is rotated. The target parameters are usually set by rotating, and the function is
started by pressing;
Type Ⅱ Knob: The knob of Standard Overhead Stirrer can be rotated. There is a stop point when
being rotated and only can be rotated more than half a circle. The target parameters are set by
rotating, by which the function is started;
1.2 Structure
FIG.4
FIG.5

3
1 Front Guard 2 Rubber Cap 3 Nail 4 Membrane
5 Knob 6 Power Switch 7 Knob Lock 8 Knob Switch
9 Master Control Board 10 Coded Disc 11 Rubber Ring 12 Shaft
13 Photoelectric switch 14 M3*10 Socket Hexagon Screw 15 Bearing 16 Belt
17 Spindle Pulley 18 Bearing 19 M4*35 Socket Hexagon Screw
20 Ø 4 Elastic Pad 21 Lower Support Plate 22 Motor Pulley 23 Motor Bearing Support
24 M4*15 Socket Hexagon Screw 25Ø 4 Elastic Pad 26 Motor
27 Rail 28 RS232 Interface 29 M5*16 Socket Hexagon Screw
30 Rear Guard 31 M3 Hexagon Nut 32 M3*6 Copper Stud 33 Ø Ceramic Gaskets
34 Driven Board 35 M3*6 Pan Head Screw 36 Power Outlet
Fig. 4 illustrates the structural components of OS40 (20)-Pro, and Fig. 5 is the Exploded View of
OS40 (20)-Pro. Guard module includes front guard, Membrane, knob, power switch, rubber cap,
LCD PCB, knob switch, and PCB clamp and so on. Control modules are consisted of rear guard,
Driven Board, power outlet, RS232 interface and bar and so on. The movement module is
composed of motor, coded disc, shaft, motor pulley, bearing pulley, bearing, belt, photoelectric
switch, lower support plate and so on.

Stirring: Motor drives shaft to rotate though pulley, and further the shaft drives stirring
impeller fixed on it to rotate. Thus, the target sample is stirred.
Speed feedback: the motor speed is accurately measured by the coded disc fixed on the Shaft
along with photoelectric switch and a feedback is given. (OS40(20)-Pro)
LCD display: LCD PCB is connected to Driven Board and displays user’s settings and current
equipment operation information.(OS40(20)-Pro)
Chapter 2: Removal and Installation of Instrument
When instrument failure occurs, first, you should conduct a failure analysis; if the failure is caused
by the damage of instrument hardware, the related component must be repaired or replaced. Here
are the relevant contents of the replacement and disassembly of instrument.
2.1 Removal
Tool：Cross screwdriver

4
Step 1:
Turn over the instrument, remove
the four screws marked red circles
and keep them to be properly
preserved. Remove the screws
marked green circles at the back of
the instrument and keep them to be
properly preserved.
Step 2:
Separate the front and rear guard,
and respectively pull out cables
marked by red circle.
The front and rear guard are
placed at the positions as shown in
the Fig., and conduct a analysis on
the failure.
Step 3:
Remove the 4 screws marked by
red circles and keep them well.

5
Step 4:
Separate the guard module and
movement module.
2.2 Main parts illustration
1 2 3 4 5 6
Item Spare part 0S20-Pro OS20-S OS40-Pro OS40-S
1 Master Control Board 18100472 18101620 18100472 18101620
2 Encoder/potentiometer 18100483 18100489 18100483 18100489
3 Driven Board 18100651 18101619 18100473 18101619
4 Motor 18100493 18100493 18100492 18100492
5 photoelectric switch 18100484 / 18100484 /
6 Belt 18200630 18200630 18200630 18200630

6
2.3 Circuit Connections (OS20-Pro&OS40-Pro)
Step 1:
Circuit connections are performed
at the red circle. Before close the
upper guard and install instrument,
please carefully check the cables
and make sure they are correctly
connected.
Power Interface
Power switch Interface
Ribbon Cable Interface of LCD PCB
Photosensor interface
Motor interface

7
2.4 Replacement of drive board
Step 1:
Pull out the cables of Driven Board.
Remove the screws and ceramic gaskets
(marked in red circles) of fixing Driven
Board by tools and keep them to be properly
preserved;
Step 2:
Turn over the old Driven Board to be
removed, and remove thermal silicagel pads
on the Driven Board, to affix it to the
corresponding position on the new PCB
control board. Pay special attention that the
silicagel pads must completely cover the
corresponding components. Then carry on
circuit connections and tighten
2.5 Replacement of Control Modules
Step 1:
Pull out the cables of control
modules and Driven Board
after the removal of the
instrument; replace new control
modules, and tighten screws
after the cables are connected;

8
2.6 Replacement of Movement
Step 1:
Remove the cables of
movement module and guard
module.Remove the screws of
movement module and guard
module at the bottom of the
instrument for retention.
Re-assemble the instrument
after new movement module is
replaced.
2.7 Replacement of Photosensor
Step 1:
Remove the screws (marked
red circles) by tools and keep
them to be properly preserved.
When you replaced new
photosensor, the coded disc on
the motor must match with
photosensor. When motor is
running, coded disc cannot be
frictional contact with
photosensor. After fine-tuned
the positon of coded disc,
fasten it with screws.