Hardy HI 2151/30WC Single-Scale Controller - Manual (Page 151)

Chapter 8 - Troubleshooting
8-31
to measure pressure, load, or torque. This can be accomplished by
either Tension or Compression type load cells/points. The load cell/
point takes as an input the 5 volts DC Excitation Voltage generated
by the HI 2151/30WC, and depending upon how much weight is
applied to the scale, generates a millivolt output (proportional to the
weight, 0-10mv DC for 2mv/V load cells/points or 0-15mv DC for
3mv/V load cells/points).
b. IT Junction Box (Prt. # HI-215IT-SS1 - Stainless Steel, HI-215IT-
PS1 - Painted, HI-215IT-FG1 - Fiber Glass) - is a system control
box used to sum the incoming and outgoing signals of from one to
four load sensors or load cells. The Junction Box distributes the
excitation voltages to each load sensor/load cell and transfers each
load sensor's performance characteristics and weight signals to the
weight controller. The IT Junction Box when used with the HI
2151/30WC allows for some automated system diagnostics. It uses
connectors for isolation and troubleshooting of the weight system.
The IT Junction Box allows an operator to automatically switch in
an internal test circuit to perform a system stability test and read the
individual load sensor voltages (in millivolts or millivolt/volt) for
up to 4 load sensors from the HI 2151/30WC front panel. Bias volt-
ages will come from the load sensor excitation voltage and will not
affect calibrated weight readings. Switching commands come over
the C2 lines from the weight controller. Nomenclature on the board
will identify positions. The user will know where load sensors 1-4
are physically located by filling out a label mounted to the inside
top cover of the IT Junction Box.
c. Weight Controller - is an electronic instrument which, among other
functions, is used primarily to power the load cell(s)/point(s), take
the millivolt signal output from the load cell(s)/point(s), and digi-
tize, interpret, communicate and display the results as a weight
indication.
No Keypad
Operation 1. Config dipswitch S3 set to keypad lockout; reposition switch.
2. Check for "HI" on display. Whenever "HI" is displayed, the keypad
will be disabled except for the Cal Menu and the -/Test/Clr buttons.
Remote Functions
Non-operational 1. Check wiring at J2.
2. Ensure correct ground is used (J2 pins 9 or 10).
3. Check for correct setting of Config dipswitch S3, See Chapter 4,
Configuration.
NOTE: The HI 2151/30WC should have a quality power conditioning product installed
between the controller and the AC power source to reduce the likelihood of faults
caused by poor or intermittent AC power.