Cal by shunt val, Counts per inch, Limits – Epson 9840 User Manual

Page 21: Imits

Advertising
background image

I N T E R F AC E M O D E L 9 8 4 0 V E R 6 . 0 . 2

set the torque. When the Model 9840 is reading the cell it will display the “Reading...”
message for about 10 seconds. During this time it is important that the masses or
torque are not disturbed since all the readings taken are averaged together to obtain
the calibration data. The second mass/torque is then entered and read. If 5 Point
calibration was selected, masses/torque three through five will be entered and read.
One of these readings should be at zero. A "No Masses Ready?” or "No Torque
Ready" reading is also required. During this reading, a shunt check value is recorded.

>>Cal by Shunt Val

This item is used to calibrate a cell using the manufacturer’s shunt calibration factor
expressed in pounds or pound-inches. You will be asked for the channel, the cell
serial number, the date, the calibration unit, the cell’s maximum rated load or torque,
the desired excitation voltage (5.0 or 10.0 volts), and the shunt calibration constant.
The Model 9840 will then automatically perform the shunt calibration of the cell using
its internal precision shunt resistor. Note that there is a back panel switch that allows
you to select either a 30K or 60K resistor for shunt measurements (see Appendix B for
a circuit diagram). Be sure to select the appropriate value for your cell. During this
calibration the “Reading...” message will be displayed. Do not disturb the cell while it
is being read. Like the “Cal by mV/volt” option, the cell should be free of load or
torque during this calibration.

>>Counts per Inch

This entry allows you to set the number of counts per inch that the quadrature encoder
input will use.

>Limits

This menu is used to set up the 4 contact closure switches. Instead of a submenu there
are a series of selections. Pressing Enter will accept the displayed entry. Pressing
Escape will return to the setup mode main menu without changing the limit setup. Note
that changing a cell type on a channel will automatically erase limits that were set for that
channel. These limits must then be reset by the user.

1. Select Limit X -- The first selection chooses which of the limits you want to set up (1-

4). Use the left/right or plus/minus buttons to change the number. Press enter to
accept the displayed number. Press escape to return to the setup mode main menu.

2. Normally Open / Closed -- This selection determines if the switch contacts are open

or closed when the limit is de-activated.

3. Enabled / Disabled -- Choosing enable allows the limit to operate as specified by the

following selections. Choosing disable places the limit in its “normal” state and
completes the limit setup.

4. Source: -- This selection allows you to scroll through a list (use either the left/right or

plus/minus buttons) to select the source of the data that will drive the limit. The
standard list will include load or torque, peak, valley, position, and velocity. Press
enter to select the displayed item.

5. Units: -- This entry allows you to scroll through the list of available units for the data

source you have chosen in the previous step.

6. Set -- This is the numerical value of the source at which the limit will be activated (set

point). It is specified in the units you chose in the previous step.

M O D E L 9 8 4 0 P G 2 0

P U B .

2 8 5 6 - 1 6

Advertising