Go To Troubleshooting Card:
“No Control Over
Field Decoders”
Short could be caused
by contact between
RED and BLACK
conductors or internal
to a decoder or LSP-1.
Single Address
Decoder = 0.5mA
multi-Address
Decoder = 1.0 mA
LSP-1 = 0.0 mA
START
Turn off all LDI field wire path
slide switches and confirm
normal LDI operation.
Open Decoder Diagnostics
window in central
control software.
Use clampmeter to check RED
and BLACK wires on upstream
or “EQUIP” end of mSP-1.
Replace mSP-1
Choose point halfway back
to central control and
measure current draw.
Confirm by using
clampmeter on single BLUE
communication wire.
Repair or replace components
as necessary.
Compare “at rest” current to
expected “at rest” current.
Run ON/OFF Test in Decoder
Diagnostics to Validate
System Operation
Repeat to narrow down
location of wire path short.
Choose point halfway
between measurement point
and end of wire path.
Break critical path wire loop
(if present). Choose point
halfway out on wire path.
Using clamp meter, check RED
and BLACK wires individually.
Compare each value to
expected current draw.
Turn Off Field wire Path
Slide Switch — Repeat
for Each Additional
wire Path
Turn on wire path slide switches
one at a time. monitor current to
verify it reaches expected
“at rest” draw for wire path.
Recommended Rain Bird
®
Troubleshooting Procedure for
“Shorted Wire Path”
OKAY
OKAY
SHORT
FOUND
CONFIRmED
COmPLETE
EQUAL
HIGH
LOw/ZERO
NOT EQUAL
No Further Action
Symptoms:
No Decoder
Operation on Wire Path or LDI.
Field LED may be solid or faint.
NOT NORmAL
HIGH “AT REST”
CURRENT DRAw
mEASURED
DOwNSTREAm
LESS THAN
UPSTREAm
UPSTREAm
EQUAL TO
DOwNSTREAm
5
