Wiring Challenge at Copper River

Posted by John Hamilton

Spaghetti FactoryWiring Mess from Hell

We were recently hired by Bill Griffith CGCS of Copper River C.C. in Fresno, CA to perform a complete control system upgrade. The scope included GPS Mapping, installation of new Toro V.P. radio based satellites and programming of the Lynx central. There was a lot of preplanning before getting onto the job site which included the mapping and the re-sequencing of stations where we broke up double and triple heads per station. We were meticulous in planning how we were going to break up the field wiring for the new Toro VP controllers. With all the careful pre-planning, sometimes you just never know what you will run up against until you are in the belly of the beast out in the field.

 

During the old satellite breakdown in preparation to pour new pads, we numbered each wire in the existing controllers to identify which station belonged where when we wired the new satellites. It was not just wire for wire and simply slapping on a new controller onto existing pads. We had the challenge of going into the bird's/rats nest where the field wires were spliced underground and had a single wire run up a sweep into the satellites.

 

We ran across one satellite which turned out to be the "Nightmare on Hell Street". This controller had been rewired multiple times as field wires were changed and re-routed when they built their clubhouse three years after the irrigation system installation. Instead of the birds nest only having some 50-60 spliced station connections, there was well over 120 wires; half of them were good and the other half was well.........not so good. All this came together and conjoined into one heaping pile like a big bowl of spaghetti. We essentially had three options to take in rewiring and re-sequencing this satellite.

 Option 'A' - Start at the existing station wires which came from the controller that we labeled and identified. From there we would dig them up and follow them back to the birds nest where they met the field wires. That way we would not have to go through the hassle of hot-posting to re-identify everything.

 

Option 'B' - Tone each wire where we could identify and relabel them within the birds nest with over 120 wires.

 

Option 'C' - Cut the birds nest apart and hot post every wire to see which wire controlled which valve.

 

After careful consideration, Option 'A' did not seem viable as the existing controller wires came out of the old satellite and traveled well away from the birds nest. Even though we had a digging crew, the wires branched off in many different directions. Option 'B' just seemed like a pain in the butt, as toning wires can become time-consuming and the tone often bleeds into other wires. I chose Option 'C', thinking how hard can hot posting wires and seeing water pop on actually be? Well, that is what I thought in all my great wisdom.

 

So there I was chopping up the birds nest, cutting wires, cleaning up two decades of over 120 station wires to do the "right thing". Oh boy, in all my great intentions, choosing Option 'C' had to be about one of the worst decisions I had ever made in rewiring a satellite.

 

I now had approximately 120 existing station wires coming up from the depths of the earth. All of which needed identification, labeling, splicing and new wires run up the sweeps and into the new satellite. As discussed, only 1/2 of these wires went to working valves in the field, and the other half was old existing junk. Which ones worked was supposed to be a simple process of elimination.

 

Working through this mess was a nightmare beyond anyone's imagination. There were about 4-5 directions that these stations wires came from and into the birds nest. Identifying which ones were good and bad became a significant challenge. I was taking a wild guesse on which bundles were good and which ones no longer worked. I stripped off each wire and scraped the ends to have clean copper to work with when it came to hot posting each one.

 

As we were hot-posting and crossing our fingers that a valve would turn on, we cross-referenced them to our newly re-sequenced maps. We found working wires which went to operational valves that would not turn on, and others which had been abandoned from the past. Some valves were manually off in the field which made things more challenging. Even after the process of elimination, we used a volt meter to see if we were reading any ohm's resistance off of the solenoid just to identify good wires from bad. At least, this helped us determine if a valve was shut off in the field. There was also black oxidation on the existing field station wires which had built up over time that would prevent positive electron flow while hot-posting. We painstakingly scraped off each stripped wire lead to overcome this challenge.

 

With so many wires jumbled up in the birds nest, it was so easy to get lost and have to start over. It was so bad that it took two of us an hour and a half just to straighten out wires into semi-manageable groups. In our great attempt, we had groups of wires which we guesstimated were 'good piles', 'bad piles', 'maybe piles', and 'WTF piles'. It was our attempt just to make order out of absolute chaos.

 

We slowly worked through the tangled mess of spaghetti before wiring up the new satellite. It was frustrating when a valve did not turn on because it had been manually turned off from irrigation personnel. The hours marched on until we realized that we had been bent over this hole for the entire day with only 1/2 of the wiring complete. On the second day we completed up to 90% as we identified and wired up each station; yet, there was still six stations left to figure out. Was it because of valves turned off in the field, corroded wires, or wires we just had not found in the birds nest. On the third day, we had the local irrigation staff checking to ensure that valves and solenoids were in proper working order. The very last station which was not working turned out to be a buried wire within the old birds nest that we luckily happened to step on.

 

After spending well over 22 hours in rewiring this monstrosity and getting everything to work in the new satellite, the superintendent came over with a black permanent marker and asked me to sign the inside of the newly installed Toro VP Satellite.

 

My recommendation to you is that if you ever have to rewire a new satellite with this type of mess..............................do yourself a favor and either pick Option 'B', or have someone else rewire the darn thing and get busy on another project which will not cause as many headaches or frustrations!