Cooper Instruments & Systems Model 7i Professional Force/Torque Indicator - Manual (Page 4)

Model 7i Digital Force / Torque Indicator User’s Guide
3
Example 1
Model MR01-100 sensor with Model 7i Indicator
MR01-100
±0.15% of full scale
+
7i
±0.1% of full scale
=
Total
±0.25% of full scale
This translates into a fixed error of up to:
0.25% x 100 lbF = 0.25 lbF
Example 2
Model MR50-50Z sensor with Model 3i Indicator
MR50-50Z
±0.35% of full scale
+
3i
±0.2% of full scale
=
Total
±0.55% of full scale
This translates into a fixed error of up to:
0.55% x 50 ozFin = 0.275 ozFin
Because accuracy is defined as a
percentage of full scale, the fixed error is possible anywhere on the
scale from 0 to the capacity. As such, this value represents an increasingly large error as percentage of
reading towards the low end of the scale. It is, therefore, recommended that a sensor is selected with
capacity as close as possible to the expected load.
The resolution may be different for some sensors depending on whether a 7i, 5i, or 3i indicator is being
used. For example, a Series R01 force sensor will display finer resolution when connected to a 7i
indicator than when connected to a 3i indicator. Resolution information is shown in the sensors’ user’s
guide.
1.4 Safety / Proper Usage
Read through the following safety instructions thoroughly before using the 7i with a sensor:
1. Note the sensor’s capacity before use and ensure that the capacity is not exceeded. Producing a
load greater than the indicated safe overload value can damage the sensor. An overload can
occur whether the indicator is powered on or off.
2. In order to extend the life of the sensor, avoid repetitive shock and impact loading.
3. When moving the sensor to another location, never lift from the cable or strain relief. This can
cause damage to the sensor. Always lift the sensor housing itself.
4. Always ensure that load is applied axially with respect to the sensor.
5. Ensure that the sensor is kept away from water or any other electrically conductive liquids at all
times.
6. The sensor and indicator should be serviced by a trained technician only. AC power must be
disconnected and the indicator must be powered off before the housing is opened.
7. Always consider the characteristics of the sample being tested before initiating a test. A risk
assessment should be carried out beforehand to ensure that all safety measures have been
addressed and implemented.