Sartorius QC34EDE-S, Service Manual

17

SARTORIUS QC - Scales

Adjusting the Span (Sensitivity)

Note:

There are two methods for adjusting the span (sensitivity):

1. As described in this manual, or
2. Using the MC1 PSION server

– Set the code “1 9 1” in the scale operating menu (external calibration

accessible).

– When 0.0g is displayed, press and hold the 

e

 key for about 3

seconds; then release it.

– The adjustment weight is displayed.

Important note:

The scale will only accept an adjustment weight that is within a tolerance of
2% of the target value.  Any greater deviation can only be adjusted using the
MC1 PSION server (Datapack version 4.4).

– Place the prompted adjustment weight on the middle of the weighing

pan.
After confirming the weight, the scale returns to the normal operating
mode.

Replacing the Main PCB

In the case of defects, do not attempt to make any repairs at the component
level, but rather replace the entire subassembly.

Note:

Before replacing the main PCB, read out and store the scale’s data records
using the MC1 PSION server, if possible.
If this is not possible, order a replacement PCB; make sure you supply the
model and serial number of the scale for programming purposes.

– Open the display unit by removing the 4 screws at the back.
– Carefully pull the front panel far enough away from the rear panel to

disconnect the 3 cables (data output, power supply and connecting
cable)
that lead to the strain gauge system.

– Remove the entire front panel.
– The main PCB is connected to the front panel by 5 screws (one in each

corner and one to ground the keypad overlay).  Remove these 5 screws.

– Remove the cable that leads to the keypad.
– You can now remove the main PCB.

Important note:

Make sure you duplicate the solder bridges from the old main PCB to the
new one!

-

Install the new main PCB (follow the above steps in reverse order).

-

Switch the scale to BPI mode.

Note:

You will now need to program the scale with the appropriate data set.
Check the following points and adjust them if necessary:

-

Zero point offset value

-

Linearity

-

Span (Sensitivity)