Hardy HI 1756-2WS - Manual (Page 12)

HI 1756-WS WEIGH SCALE MODULE
1-4
between the module, Remote Terminal Assembly
(RTA) and the IT
®
Junction box. If the measured cur-
rent deviates more than a ± 10% tolerance, an “Exci-
tation Error” bit (Module Status Word bit 9) is set to
1.
Digital Volt Meter
(DVM) - Optional Requires the HI 215IT Series Junction Box to monitor
both mV and mV/V readings for the system and per
individual load sensor. Once a problem is detected by
the operator the DVM readings help the operator to
isolate the faulty component. Further, the DVM read-
ings can be used to level a system and to make corner
adjustments to platform scales. Accuracy is +/- 2% or
better of full scale.
NOTE: If you do not have the HI 215IT Junction Box con-
nected to the module, the mV/V reading as displayed
is the total for all the load cells on the system.
Return to Zero
Test - Optional Requires the HI 215IT Series Junction Box to monitor
individual load sensors. This test compares the origi-
nal voltage reading (saved at calibration) against the
current voltage reading of an empty vessel. The test
checks for damaged load sensors due to electrical zero
shift or abnormal mechanical forces that cause bind-
ing on one or all of the load sensors in the system.
Weighing System
Tests - Optional Requires the HI 215IT Series Junction Box for full
utilization. This test is used to diagnose drifting or
unstable weight reading problems. The Weighing Sys-
tem Test does the following:
1. Disconnects the controller and engages an inter-
nal reference signal to see if the problem is within
the instrument.
2. Disconnects the load sensors and engages an
internal (in the junction box) reference signal to
see if the cable between the instrument and the
Junction Box is causing the problem.
3. Reads the weight of each load sensor to see if the
load sensor might be causing the problem.