SKC Limited SPLIT2 - Manual (Page 21)

21
SPAN CHECK USING THE CALIBRATION POST
Span Check
Span checks should be performed once per month, but if the
instrument has been dropped or knocked, a span check should
be carried out immediately.
The SPLIT2 MUST be reset to its defaults.
You must then perform the Auto-Zero sequence, see page 13.
Once the Auto-Zero has finished remove the Zero-Filter and
sampler inlet if fitted.
Insert the Calibration Post making sure the location pin is lined
up with corresponding hole in the sensor head. The easiest way
to do this is to push the calibration post into the sensing head
and while maintaining forward pressure, turn the post until you
feel it locate. Once located the post will not twist from side to
side.
Finally run the unit on the RUN OVERWRITE option for at least
2 minutes. The display will show a figure of around 200.00
Compare the displayed figure to the K Factor printed on the
calibration post. If the difference between these two figures is
more than +10% repeat the above procedure.
If the difference is still greater than + 10% you have two options.
1. Correct for the difference by entering a value in to the SCALE
option. see p19
2. Return the SPLIT2 for a recalibration and service.
Location Pin
Calibration Post
* SCALE *
Scale: 00.90
Span Check correction:
After a Span Check you find the displayed value to be greater
than +10%.
To correct for the difference use the following calculation.
Example:
Displayed value is 180.00
K Factor is 200.00
180
200
=0.9
= SCALE
Displayed value
K Factor from calibration post
‘K’ Factor
Sensing head
Calibration Post
Zero Filter