Nexen RSTC1000 964523 - Manual (Page 15)

FORM NO. L-21208-C-0908 12
When calibrating the tension sensor signal, the registers for each calibration set must be written in the order shown
here.
Calibration Set 1
94 – 95: Tare Tension Floating point number sent as long integer * 1000 in units of lbs, read & write. Tare Tension is
typically set to 0 and represents the web tension at the tare condition when the load cells measure only the weight of
the tension sensing roller and its associated hardware.
Example: 324.742 lbs
Register 94: 4 (msw)
Register 95: 62598 (lsw)
Tare Tension = ((4 * 65536) + 62598) / 1000 = 324.742 lbs
96 – 97: Span Tension Floating point number sent as long integer * 1000 in units of lbs, read & write. Span Tension
has a range of 1 to 10,000 lbs and represents the load seen by the load cells when a known web tension is applied
that is less than the Maximum Tension Setpoint.
Example: 350.000 lbs
Register 96: 5 (msw)
Register 97: 22320 (lsw)
Span Tension = ((5 * 65536) + 22320) / 1000 = 350.000 lbs
93: Load Cell Measure Flag Sent as integer, read & write. Load Cell Measure Flag is only used after Tare Tension
and Span Tension registers have been written.
1. Remove any web tension from the tension sensing roller and then write a 1 to Load Cell Measure Flag. This
calibrates the load cell tare condition.
2. Read Load Cell Measure Flag to determine when previous calibration step is complete. Under normal condi-
tions, the tare calibration takes 10 seconds. Calibration step is complete when fl ag = 0.
3. Apply the web tension load that was sent to Span Tension register and then write a 2 to Load Cell Measure
Flag. This calibrates the load cell span condition.
4. Read Load Cell Measure Flag to determine when previous calibration step is complete. Under normal condi-
tions, the span calibration takes 6 seconds. Calibration step is complete when fl ag = 0.
5. Remove any web tension from the tension sensing roller and write a 3 to Load Cell Measure Flag. This checks
the load cell tare condition.
6. Read Load Cell Measure Flag to determine when previous calibration step is complete. Under normal condi-
tions, the tare check takes 2 seconds. Calibration step is complete when fl ag = 0.
Load Cell Calibration Set 1 is now calibrated.
Calibration Set 2
98 – 99: Tare Tension Floating point number sent as long integer * 1000 in units of lbs, read & write. Tare Tension is
typically set to 0 and represents the web tension at the tare condition when the load cells measure only the weight of
the tension sensing roller and its associated hardware.
100 – 101: Span Tension Floating point number sent as long integer * 1000 in units of lbs, read & write. Span
Tension has a range of 1 to 10,000 lbs and represents the load seen by the load cells when a known web tension is
applied that is less than the Maximum Tension Setpoint.
93: Load Cell Measure Flag Sent as integer, read & write. Load Cell Measure Flag is only used after Tare Tension
and Span Tension registers have been written.
1. Remove any web tension from the tension sensing roller and then write a 4 to Load Cell Measure Flag. This
calibrates the load cell tare condition.
2. Read Load Cell Measure Flag to determine when previous calibration step is complete. Under normal condi-
tions, the tare calibration takes 10 seconds. Calibration step is complete when fl ag = 0.
3. Apply the web tension load that was sent to Span Tension register and then write a 5 to Load Cell Measure
Flag. This calibrates the load cell span condition.