Cooper Instruments & Systems DFI 1650 Multi-Channel Digital Force Indicator - Manual (Page 37)

CF 66 31 Rev. C 2/05
KNOWN POINT x/y Menu Items
This enters the engineering units for the known-load calibration points. These points must match the actual loads
that you will apply to the instrument during calibration. The number of calibrations points depends on the
CALIBRATION TYPE.
When using the 2-Point Known Load Calibration type, the following menu items are available:
• “KNOWN POINT 1/2”: point 1 of 2, usually 0% of the transducer’s full-scale capacity.
• “KNOWN POINT 2/2”: point 2 of 2, usually 100% of the transducer’s full-scale capacity.
When using the 3-Point Known Load Calibration type, the following menu items are available:
• “KNOWN POINT 1/3”: point 1 of 3, usually 0% of the transducer’s full-scale capacity.
• “KNOWN POINT 2/3”: point 2 of 3, usually 50% of the transducer’s full-scale capacity.
• “KNOWN POINT 3/3”: point 3 of 3, usually 100% of the transducer’s full-scale capacity.
When using the 5-Point Known Load Calibration type, the following menu items are available:
• “KNOWN POINT 1/5”: point 1 of 5,usually 0% of the transducer’s full-scale capacity.
• “KNOWN POINT 2/5”: point 2 of 5,usually 25% of the transducer’s full-scale capacity.
• “KNOWN POINT 3/5”: point 3 of 5,usually 50% of the transducer’s full-scale capacity.
• “KNOWN POINT 4/5”: point 4 of 5,usually 75% of the transducer’s full-scale capacity.
• “KNOWN POINT 5/5”: point 5 of 5,usually 100% of the transducer’s full-scale capacity.
To insure both correct operation of the transducer and application of the load, the instrument expects the voltage
applied at each know-load point to be increasing. For example, the load applied at Known-Load Point 2/2 must
cause the transducer to produce a more positive voltage than at Known-Load Point 1/2.
These menu items are only available with the Known-Load Calibration types.
10.5.6 CALIBRATE Menu Item
This menu item performs a calibration according to what was entered in the CALIBRATION TYPE and
CALIBRATION DATA menu items.
Before performing a calibration, the transducer must be connected to the instrument, the CALIBRATION TYPE
must be selected (see “CALIBRATION TYPE Menu Item”), and the CALIBRATION DATA must be entered (see
“CALIBRATION DATA Sub-Menu”).
For maximum accuracy, allow at least twenty minutes of warm-up with the excitation voltage applied to the
transducer before calibration.
If the CALIBRATION TYPE is Shunt Calibration…
• The display will read DOING SHUNT CAL, and prompt you to APPLY 00000 UNIT (where 00000 and UNIT are
previously entered as ZERO SCALE VALUE and DISPLAY.UNITS. When you have applied this load to the
transducer, press [ENTER].
• The display will then read WORKING and calibration will take place. Upon completion, the display will indicate
DONE and the instrument will return to the RUN mode.
If the CALIBRATION TYPE is mV/V Calibration…
• The display will read DOING MV/V CAL, and prompt you to APPLY 00000 UNIT (where 00000 and UNIT are
previously entered as ZERO SCALE VALUE and DISPLAY.UNITS). When you have applied this load to the
transducer, press [ENTER].
• The display will then read WORKING and calibration will take place. Upon completion, the display will indicate
DONE and the instrument will return to the RUN mode.
If the CALIBRATION TYPE is 2-Point Known Load Calibration…
• The display will read DOING 2POINT CAL, and prompt you to APPLY 00000 UNIT (where 00000 and UNIT are
previously entered as KNOWN POINT ½ and DISPLAY.UNITS). When you have applied this load to the
transducer, press [ENTER].