Rain Bird MDC2, Instructions Manual, Page: 83 / 124

Troubleshooting
77
Understanding Faults
Faults are error conditions that can occur in any electronic system or equipment, no matter how well designed
and built. Many factors can contribute to faults, such as the system’s age, natural occurrences (i.e., lightning,
floods, frost or heat), or human errors.
When installing the MDC2 Controller and irrigation system, human errors can and do occur. They happen by
overloading cables and sockets, adding excessive pressure to decoders, solenoids, or cables with heavy equipment
(tractors or cultivators), or not taking the necessary care when connecting the systems cables and decoders.
Fortunately, the MDC2 Controller and irrigation system features built-in test diagnostics to help pinpoint specific
faults and to aid in troubleshooting.
Finding the Cause
This chapter of the manual is written for you, the Service Technician in the field. It is your responsibility to
localize problems with the Rain Bird
®
MDC2 Controller and Rain Bird
®
Decoder Irrigation System and determine
their cause. You should always find the fault and correct it in the field at the “box” level. In other words, if you find
the fault in a field decoder, replace the field decoder. If you find a fault inside the controller, replace the controller.
Only highly qualified Rain Bird
®
Service Technician Specialists should find and correct problems inside a “box”
(replace worn out or defective components inside a controller, decoder, solenoid, etc.).
The purpose of this chapter is to teach you basic troubleshooting techniques that you can easily do in the field.
This chapter does not cover faults that were caused by using the wrong size cable (wires that are too thin or cable
lengths that are too long) or faults caused by entering incorrect data into the controller.