POWER/ERROR
PC -> DATA
DATA -> PC
24V-AC MAINS
@ 2A GND
SENS-1
SENS-2
EARTH
1A-1B 2A-2B 3A-3B 4A-4B
OFF
ON PC-COM
LINE
ON
OFF
Troubleshooting
Decoders
Use one or two screws at the top and one at the
bottom, depending on support.
On when power is on. LED is controlled by
processor. Will not turn on if no firmware is
downloaded. Blinks when there is an error
condition (see below).
CAUTION
Mains- and system-ground are
not internally connected and must
be separated to provide the best
protection against surges.
Normally off. Blinks when data is
received
from PC.
Normally off. Blinks when data is
sent
to PC.
Line indicator, toggles between red and green with
line voltage polarity.
Switches for disconnection of line with problem.
Serial cable, 9 PIN-9 PIN for PC communication.
Field wires. Up to four two-wire paths may be
connected.
INSTAllATION DeTAIlS
(LARGE AND SmALL DECODER INTERFACE)
lOCATING A BAD DeCODeR uSING A ClAmp meTeR
SENSOR 1 (e.g. Rain Sensor)
SENSOR 2 (Not Shown) (e.g. Alarm Sensor)
To System Ground
Connect to 24 VAC
transformer
During power up, the LED’s will blink in sequence ending with POWER LED on for 5 seconds.
If the POWER LED blinks, it means that an
error
is detected by the unit. The reason for the error is indicated by the other LED’s:
• If
DATA->PC
is
ON
= line voltage has been switched off because connection to the PC is lost.
• If
LINE
is
ON
= line voltage is below 25 V (short).
• In the Decoder Diagnostics screen select 60Hz test mode to allow the clamp meter to measure current. When done with
troubleshooting remember to cancel the 60Hz test mode to resume irrigation.
VOLT METER
33 VOLTS ± WHEN IN 60Hz TEST MODE
33v±
0.5±
1.0±
0.5±
BAD
DECODER
CAM
CLAMP METER
HIGHER
THAN
CAL
CULA
TED
VA
LU
E
HIGHER
THAN
CAL
CULA
TED
VA
LU
E
HIGHER THAN
CALCULATED VALUE
HIGHER
THAN
CAL
CULA
TED
VA
LU
E
LESS
THAN
CAL
CULA
TED
VA
LU
E
LESS THAN CALCULATED VALUE
HIGHER THAN
CALCULATED
VALUE
4
