Rain Bird FD-101, FD-102, FD-401, FD-202, FD-601 Troubleshooting Manual

Troubleshooting

Decoders

Rain Bird® Decoders

Decoders are a cost-effective alternative to traditional in-field controllers.

Installed underground and featuring simple, low-cost wiring, decoders are

an aesthetically pleasing and economical option for reliable, in-field control.

Installation requires up to 80 percent less wire than conventional controller

systems. Electronic components are completely encapsulated to protect

against the elements. And system expansion is easy: simply splice into the

communication line to add additional decoders.

Learn more about this simple, reliable technology and how to service it in

the following topics:

• General Information

• No Control Over Field Decoders

• Shorted Wire Path

• Suspected Broken Wire Path

• Suspected Ground Fault

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Troubleshooting

Decoders

General Information

Calculate expected “At Rest” current

draw on each wire path and each

LDI or SDI interface.

• FD-101 = 0.5 mA

• FD-102 = 0.5 mA

• FD-202 = 1.0 mA

• FD-401 = 1.0 mA

• FD-601 = 1.0 mA

Prior to troubleshooting when using

a clamp meter, make sure you know

the static current draw of the wire

path or sections of wire path you will

be troubleshooting. (1) To calculate

the static current draw at an individual

wire path section, add the number of

decoders that are downstream from the

test point, and multiply it by the current

draw of each decoder to determine

the total calculated current draw of

the wire section after the test point. (2)

To calculate the static current draw of

an entire wire path, add the number

of decoders on the entire wire path,

and multiply it by the current draw of

each decoder to determine the total

calculated current draw of the wire path.

(3) To calculate the static current draw of

an entire interface, add up all calculated

wire path current draws that are

connected to the interface.

Example:

BLUE WIRE

• 100 FD-101 x 0.5 mA = 50 mA

• 25 FD-202 x 1.0 mA = 25 mA

• 10 FD-401 and FD-601 = 10 mA

• Total Blue Wire current = 85 mA

RED WIRE

• 80 FD-102 x 0.5 mA = 40 mA

• 20 FD-202 x 1.0 mA = 20 mA

• 15 FD-401 and FD-601 = 15 mA

• Total Red Wire current = 75 mA

• Total Current for LDI or SDI = 85 +

75 = 160 mA

Tool List

• Spare Decoders

• Clamp Meter (current specifications are

available by calling 1-866-GSP-XPRT)

• Digital Multi-Meter

• Direct Bury Wire Splice Kits

• Maxi Wire Strippers

• Wire Strippers

• Linesman Pliers

• Extra Maxi Wire

• Updated “As-Built” drawing (“As Built”

should show wire path colors, decoder locations,

expected current draw per wire path and expected
current draw per LDI/SDI.)

NOTE: If the wire path has been looped,

you must break the loop in order to

properly troubleshoot current draw

using a clampmeter.

(see Locating A Bad Decoder on page 4).

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STAR T

Recommended Rain Bird®

Troubleshooting Procedure for

“No Control Over

Field Decoders”

Symptoms: No control over field
decoders and zeros in course log.

Check switch and incoming

power at 120VAC.

OKAY

Check incoming 24VAC.

OKAY

Replace LDI/SDI

If replacing transformer,
connec t 24VAC wires to
termin al screws be fore
plugging transformer in.

Replace Fu se Replace Transformer

OFF

BAD

Check Transformer Fuse

BLOWN GOOD

Verif y Power LED is on

OKAY

Confirm Sy stem Status is O K
in centr al control so ftware.

OKAY

BAD

Troublesh oot as

Necessary

Turn off wire p ath

slide sw itch and cyc le power.

SOLID LED

Replace L DI or SDI

Turn on one fie ld

wire pat h at a

time to fin d wire

path wit h short

condition. LED
will be so lid when
short ed wire path

OKAY

is activated.

SOLID LED

Check fie ld LED for

alternating GREEN/RED colors

every 0.5 seconds.

OKAY

Start 50/6 0Hz test in Dec oder

Diagnostic section of central

control software.

Verif y output volt age on each

wire pat h is 33± VAC.

OKAY

Run ON/OFF Test in D ecoder

Diagnostic Section of

Central Co ntrol Soft ware

and Proce ed to Field

Troubleshooting

expec ted and act ual “at rest ” current
draw in De coder Diagn ostic sec tion of

LOW

Disconnect

field wires and

recheck voltage.

LOW

Replace LDI/SDI

OKAY

Reconn ect field wir e. Compare

central control software.

Procee d to Field

Troubleshooting

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