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ESP-LXIVM Controller Troubleshooting Guide
Ground Fault
A ground (earth) fault can be caused when a 2-wire path conductor
is leaking to ground, possibly due to a bad wire splice, or a nicked or
damaged cable. This issue may come and go depending on the soil
moisture level. When the soil is very wet the problem will be worse than
when the soil is dry.
Controller Diagnostics
1.
Turn dial to Diagnostics / Diagnostics / Control Output.
2.
Select Controller. Note the Milliamp (mA) reading. The mA
reading will be higher than normal when current is leaking
to ground. You must know the number and type of each
device in the system to know what the mA reading should be
reading (see the Total System Milliamp Draw section for more
information).
3.
Disconnect each 2-wire path cable one at a time from the
controller IVM 2-Wire Interface Module. Recheck the Control
Output to isolate which segment of the 2-wire path has the
ground fault.
4.
Find a device location about half-way down the 2-wire path
cable. Disconnect the splices.
5.
Check the Control Output to see if the ground fault has been
isolated. If the Control Output is normal, the problem is
downstream of this location. If the Control Output still shows
the ground fault, the problem is between this location and the
controller. Keep disconnecting segments of the 2-wire path
until you isolate the problem.
2-Wire Path Diagnostics
1.
Turn the controller dial to Diagnostics / Diagnostics / Test
Shorted Path.
2.
Use a Clamp Meter to measure the Amp Draw of the 2-wire
path cable conductors at various splice locations. Note any
discrepancy in the readings. You must know the number and
type of each device downstream to know what the mA reading
up should be reading (see the Total System Milliamp Draw
section for more information).