Rain Bird Gold LINK 900, Руководство пользователя, Страница: 27 / 35

26
September 2015
If only a single controller is showing issues (note that the
diagnostics could be showing issues with multiple channels as a
PAR+ES can use up to 3 channels), look at the Link Diagnostic and
try to determine if it is a receiving or transmitting issue.
o
Have site conditions changed (New trees, lightning occurred, etc.)?
If there are multiple channels using the same radio (ex.: PAR+ES
with 3 channels) and the lower channel number has poor
diagnostics, it could indicate a poor signal strength issue. When the
radio first receives a signal, it is in standby mode and may miss the
first digit of message sent by the MIM/TWI.
2. MIM / TWI Troubleshooting
Inside the MIM-LINK / TWI-LINK, the LINK900 radio is connected via a 9-Pin ribbon
cable to the Output Board. On the right edge of the Output Board are four light emitting
diodes (LEDs) indicating the current communication status
•
RXD – Receive Data Indicator (Top LED)
o
Normally ON when idle. Will blink when data is being received
o
RXD can flash during transmit or when noise is present
•
CD – Carrier Detect (2
nd
LED from top)
o
Normally ON when idle
o
Off when signal detected
o
If blinking when no output occurring, interference likely
•
TXD – Transmitted Data (3
rd
from top)
o
Normally ON, blinks when data is transmitted
•
RTS – Push-to-Talk (bottom LED)
o
ON when idle
o
OFF when radio is transmitting
When troubleshooting, make sure that the LEDs react accordingly when the MIM / TWI
is transmitting or receiving.
Check the MIM CPU fuse for abnormal heat or if it is blown. This fuse is on the top right
of the CPU board while looking at the back side of the MIM/TWI door while it is open.
Check the Link Output Board fuse as well. This fuse is located on the board mounted
inside the MIM/TWI (not on the door).
Remember that the MIM-LINK / TWI-LINK will poll 8 channels every two minutes when
the system is idle. It is easiest to do troubleshooting when the system is idle (no
irrigation) as the expected Transmit / Receive patterns can be predicted.
3. PAR+ES Controller Troubleshooting
When trying to troubleshoot a PAR+ES with LINK900 radio, it is a good idea to
synchronize a watch with the time on the central control computer. When the system is
idle, the MIM/TWI will poll 8 channels every two minutes, at even minutes. Knowing
when this polling happens while in the field is useful for troubleshooting. Also, cycling
power to the controller can help resolve “frozen” radios. The TXD LED on the radio
should briefly flash and the Sync LED should turn solid after a few seconds (see below).