FMS CMGZ411, Руководство по эксплуатации, Страница: 18 / 40

Operating Manual CMGZ411/421
18
For all formulas,
γ
will be the wrap angle and
δ
will be the
angle between measuring web axis and resulting force F
M
.
9.2 Initial operation of measuring amplifier CMGZ421
Simulating method (recommended)
The following operating instructions describe operation and calibration in the machine; the web tension can
be simulated by a weight.
•
Connect both sensors
•
Check, if a positive value is displayed when loading the sensors in
measuring direction. If not, change terminals z6 / z8 resp. d6 / d8 (2
/ 3 resp. 7 / 8 with CMGZ421.E) at the controller.
•
Press key "PARAMETER" for 3 seconds
•
Select parameter „nominal force“ with
↑
or
↓
keys. Confirm with
↵
key , input nominal force of the sensors with
↑ ↓ ←
keys and
confirm with
↵
key.
•
Insert material or rope loosely into the machine.
•
Select parameter „Find offset channel A“ with
↑
or
↓
keys. Press
↵
key for 3 seconds. The electronic calculates automatically the offset
value and stores it under parameter „Value offset-feedback channel A“.
•
Select parameter „Find offset channel B“ with
↑
or
↓
keys. Press
↵
key for 3 seconds. The electronic
calculates automatically the offset value and stores it under parameter „Value offset-feedback channel B“.
•
Load material or rope with a defined weight
•
Select parameter „Calibration Feedback channel A“ with
↑
or
↓
keys and confirm with
↵
key. Input the
force referring to the applied weight with
↑ ↓ ←
keys and confirm with
↵
key. The electronic calculates
automatically the new gain value and stores it under parameter „Value gain-feedback channel A“.
•
Select parameter „Calibration Feedback channel B“ with
↑
or
↓
keys and confirm with
↵
key. Input the
force referring to the applied weight with
↑ ↓ ←
keys and confirm with
↵
key. The electronic calculates
automatically the new gain value and stores it under parameter „Value gain-feedback channel B“.
•
Go back to initial screen with „HOME“ key.
Mathematical method
If the web tension cannot be simulated, calibration has to be done by calculation. This way of calibrating is
less accurate because the exact angles are often unknown and the effective mounting conditions, which
usually deviate from the ideal, are not taken into account.
For this purpose, the offset has to be adjusted as described above. The gain factor has to be calculated by the
following formulas and then entered under parameter „Value gain-feedback channel A“ and parameter
„Value gain-feedback channel B“.
There are the following cases:
CMGZ421 with 2 Force measuring bearings
Gain feedback ch.A = 0.5 .
sin
δ
* sin(
γ
/2)
Gain feedback ch.B = 0.5 .
sin
δ
* sin(
γ
/2)
For all formulas,
γ
will be the wrap angle and
δ
will be the
angle between measuring web axis and resulting force F
M
.
With this setup, the display will show
the effective web tension value