20
14. Performance Inspection
Conduct performance inspection in a room at a temperature of approximately 25°C without large
fluctuation. Perform this inspection as a guide to judge the proper operation of the balance.
Preparation
Repeatability (1)
(2)
(3)
Cornerload error
(1)
(2)
- Warm up the balance for more than 30 minutes after turning on the power.
- The inspection should be conducted with the gram display. If another unit is
displayed, press the [UNIT] key to switch to the gram display.
- Select the following conditions in menu selection.
Response mode
A-2
(Normal)
Internal stability detection width
P-1
or
P-2
Zero tracking
d-oFF
(off)
- Perform preliminarily loading, and then press the [TARE] key to zero the
display.
Repeat loading and unloading a weight close to the capacity 10 times and record
the following values.
Xi: the value at which the display stabilizes after loading
Yi: the value at which the display stabilizes after unloading
Obtain the standard deviation
σ
x
and
σ
y
using the equation below.
9
)
(
10
1
2
∑
=
−
=
i
x
Xi
Xi
σ
9
)
(
10
1
2
∑
=
−
=
i
y
Yi
Yi
σ
Both
σ
x
and
σ
y
should be within 1.5 times the standard deviation indicated in “17.
Specifications”.
Load a weight of approximately 1/4th the weighing capacity in the order of the
numbers in the diagram below and record the values X1 to X5.
The differences between the value at the center of the pan (X1) and other values
(X2 to X5) should be within 3 times the minimum increment.
