Hardy HI 1769-FC - Manual (Page 66)

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Chapter 7
J - Electrical Inspection
1) Verify the proper input power, AC or DC, is properly installed
2) Use a meter to verify neutral, ground and hot are correct
3)
4)
Isolated from SCR and motor control circuits
Use a Common earth ground.
J
(a) Keep ground cable runs as short as possible
(b) Excessive ground cable runs can act as an antenna
for AC noise
(c) Install grounding straps around load cells to direct
static away from the load cell and directly to ground
(d) Install ground straps on the input and discharge
piping and the vessel to a common earth ground
J1
Verify the proper voltage
level has been supplied
J2
Apply power to the
controller only if supply
voltage is correct
1) Verify the front LEDS illuminate
2) Completes the initialization process
3) Reads the weight. This weight value will not be
correct if a calibration procedure was not performed
J3
Does the scale reflect
a weight change?
1) Read the NET weight
2) Send a TARE command to ZERO the NET weight
3) Apply weight to the vessel
DO NOT POWER UP THE CONTROLLER UNTIL
INPUT VOLTAGES CAN BE VERIFIED
(a) Does the weight increase and decrease in the
correct direction with the weight?
(b) Does the weight return to ZERO NET?
(c) The weight value will not be correct until a proper
calibration is complete
J4 Cabling
1) Use the load cell certificate, manuals or drawings to verify the
load cell color code. Input = Excitation, Output = Signal
2) Shielding
(a) Grounded only at the rate controller
(b) Continuous shield connection from the load cell cable
to the controller. Single point EMI/RFI drain
(c) Terminated but not grounded at the summing box
3) Sense lines installed?
(A) Jumpers or sense lines in the J1 connector?
(B) Sense lines must be installed for C2 or Softcal
calibration
4) Use IT TEST to verify readings
To Verify Proper Load Cell
Operations Go to
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