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avernon0112
05-26-2012, 01:25 PM
I have a RB MDC2 controller that shows a short circuit. I have identified which pair of wires the fault is on. I need to pick up a clamp meter to help with the troubleshooting. What kind of meter do you like?
This is the first problem I have ran into with the two wire systems. I have read some of threads here and it does not seem like it will be too complicated. If any of you have any tips they would be greatly appreciated!

Mike Leary
05-26-2012, 01:56 PM
If you're going to be doing any electrical measuring, get a Fluke, they'll last forever.

http://www.flukemeters.com

1idejim
05-26-2012, 03:23 PM
I have a RB MDC2 controller that shows a short circuit. I have identified which pair of wires the fault is on. I need to pick up a clamp meter to help with the troubleshooting. What kind of meter do you like?
This is the first problem I have ran into with the two wire systems. I have read some of threads here and it does not seem like it will be too complicated. If any of you have any tips they would be greatly appreciated!

for the money vs quality i prefer the armada pro-93 http://armadatech.com/Pro93 i have had good luck with the armada products and their product support :)

Mike Leary
05-26-2012, 03:28 PM
for the money vs quality i prefer the armada pro-93 http://armadatech.com/pro93 i have had good luck with the armada products and their product support :)

rep..............

1idejim
05-26-2012, 03:43 PM
rep..............

big nose :laugh::laugh::laugh:

tell you the joke later boss :laugh:

Wet_Boots
05-26-2012, 05:07 PM
You could score a decent leakage meter on the internet, and spend about a hundred bucks.

Kiril
05-26-2012, 05:14 PM
rep..............

How many times have I told you dad ........_________________REP_________________

Kiril
05-26-2012, 05:15 PM
You could score a decent leakage meter on the internet, and spend about a hundred bucks.

Does it also detect leaking brain matter?

Mike Leary
05-26-2012, 05:20 PM
How many times have I told you dad ........_________________REP_________________

I know, I know, I tried to get back, Loretta, but too late with my crappy internet connection up here in the woods. :cry:

Sprinkus
05-26-2012, 06:47 PM
I had a decoder fail in a short circuit condition before. Keep that in mind as you troubleshoot.
In addition adding valve solenoids in series with the wire path may allow the controller to come out of short circuit mode, which might allow you to locate the fault easier.
Was there any additional info in the fault log that might be helpful?

avernon0112
05-26-2012, 08:44 PM
I had a decoder fail in a short circuit condition before. Keep that in mind as you troubleshoot.
In addition adding valve solenoids in series with the wire path may allow the controller to come out of short circuit mode, which might allow you to locate the fault easier.
Was there any additional info in the fault log that might be helpful?

The only thing that the controller said was short circuit. No other information. I wish it was a TUCOR RKD and not this thing.

Sprinkus
05-26-2012, 09:41 PM
So there are multiple sets of 2-wire paths coming into the controller?
I've not worked with the MDC, which is probably a blessing from what I understand, so does it have a setting to read the voltage/current on the 2-wire path?
I've had some success using this function alone to locate which individual wire of a 2-wire path was causing the problem. If it's both wires of the 2-wire path I would be looking for a true short circuit condition rather than a ground fault condition.

Irrigation Contractor
05-26-2012, 09:54 PM
If it's both wires of the 2-wire path I would be looking for a true short circuit condition rather than a ground fault condition.

Bingo, and start by locating the first splice of the 2 wire path and cut that connection loose. Do some research or tracking to verify if the wire path is looped, and if it is not then just connect one leg to begin troubleshooting.

Bad decoders will give you a high current value and do not forget to check the master valve or pump start decoders if applicable.

Mike Leary
05-26-2012, 10:03 PM
Bingo, and start by locating the first splice of the 2 wire path and cut that connection loose. Do some research or tracking to verify if the wire path is looped, and if it is not then just connect one leg to begin troubleshooting.

Bad decoders will give you a high current value and do not forget to check the master valve or pump start decoders if applicable.

A perfect example of why I considered two-wire, but never installed it. :dizzy:

avernon0112
05-26-2012, 10:23 PM
So there are multiple sets of 2-wire paths coming into the controller?
I've not worked with the MDC, which is probably a blessing from what I understand, so does it have a setting to read the voltage/current on the 2-wire path?
I've had some success using this function alone to locate which individual wire of a 2-wire path was causing the problem. If it's both wires of the 2-wire path I would be looking for a true short circuit condition rather than a ground fault condition.

It does has two two wire paths on this controller. One goes to the right of the controller and the other to the left. The path is not looped. If I unhook path 2 the fault clears so it has to be in that set.
The controller show 38v and 51 ma if I remember correct.the other was 38v and 26 mA

avernon0112
05-26-2012, 10:27 PM
Bad decoders will give you a high current value and do not forget to check the master valve or pump start decoders if applicable.

no pump starts or master valves on this one. It would be easy to forget those.

Sprinkus
05-26-2012, 10:36 PM
Those readings don't seem to me like they would cause a short circuit condition.
Try connecting one individual wire of the 2-wire path that is causing the problem and see if that creates the short circuit condition. If one individual wire cause the problem then I would be thinking ground fault. If it takes both wires to do it I would be thinking defective decoder/sensor decoder/surge suppressor.

avernon0112
05-26-2012, 10:50 PM
Those readings don't seem to me like they would cause a short circuit condition.
Try connecting one individual wire of the 2-wire path that is causing the problem and see if that creates the short circuit condition. If one individual wire cause the problem then I would be thinking ground fault. If it takes both wires to do it I would be thinking defective decoder/sensor decoder/surge suppressor.

I will try that. I am going out to the site again Next week. If I find something I will post some pictures. I have a good feeling it will be a wire issue. There was lots of digging and boring on the site over winter. I know it was hit one time and repaired. I had 17 hours in repairing zone lines that they hit and left.

Irrigation Contractor
05-27-2012, 12:56 AM
A perfect example of why I considered two-wire, but never installed it. :dizzy:

To be honest, it really is more why you need to think twice before working on an existing 2 wire system:hammerhead:

We have installed over 50 decoder systems with minimal issues at best.

QUALITY CONNECTIONS WITH QUALITY WIRE SPLICES!!!!! is the key along with the correct surge and grounding protection. I would say 90% of the systems we did not install, but got the call to "maintain" (which really means the other guys could not troubleshooting the wiring) have ZERO surge protection. Then add poor connections you do have a nightmare.

We install 2 wire on any 25 gpm system over 20 zones especially with the Hunter DUAL in play now. Pulling the wire is so easy for the installers, take away all the splice boxes, pulling through sleeves and minimal planning the labor gained over rides the material costs.

I do not see how anyone does 40 plus zones anymore using conventional wire and being able to propose a competitive bid these days? My techs have had to repair so much junk from others, that when one of our installs have an issue it is solved in less than a hour.

I do not want to be labeled a rep (so I will not mention any brands), but having a TDR now is almost like cheating:cool2:

Our company had been labeled with many of the management companies as the ones to call when the words 2-wire or decoder are even mentioned. I am not kidding here, get to know these systems and get paid $$$$.

avernon0112
05-27-2012, 09:09 AM
To be honest, it really is more why you need to think twice before working on an existing 2 wire system:hammerhead:

We have installed over 50 decoder systems with minimal issues at best.

QUALITY CONNECTIONS WITH QUALITY WIRE SPLICES!!!!! is the key along with the correct surge and grounding protection. I would say 90% of the systems we did not install, but got the call to "maintain" (which really means the other guys could not troubleshooting the wiring) have ZERO surge protection. Then add poor connections you do have a nightmare.

We install 2 wire on any 25 gpm system over 20 zones especially with the Hunter DUAL in play now. Pulling the wire is so easy for the installers, take away all the splice boxes, pulling through sleeves and minimal planning the labor gained over rides the material costs.

I do not see how anyone does 40 plus zones anymore using conventional wire and being able to propose a competitive bid these days? My techs have had to repair so much junk from others, that when one of our installs have an issue it is solved in less than a hour.

I do not want to be labeled a rep (so I will not mention any brands), but having a TDR now is almost like cheating:cool2:

Our company had been labeled with many of the management companies as the ones to call when the words 2-wire or decoder are even mentioned. I am not kidding here, get to know these systems and get paid $$$$.
In the 5 two wire systems I have worked on only two of them were grounded right. Those that were grounded had only been done after it was hit by lightening. We had another company that is a all irrigation company do the work. I think it was 80 ish decoders and a controller. I really would like to become one of the people that really knows these two wire systems.

Have you had good luck out of your TDR. I have been reading Jim's post about them and thinking of picking one up.

Irrigation Contractor
05-27-2012, 10:59 AM
We have had very good luck with the TDR, but it is an addition to locators and a good clamp meter.

We just had a 180 zone system with a pump start, flow sensor, no surge and it got a small zap from a storm.

Current value was so high the system would not fire the pump start. My guys will use the locator to track the wire path, then use the clamp meter to narrow down which "legs" of the wire path have issues and continue using it until they know which path.

In this instance, we have two 4 zone decoders down, one single and the concrete contractor nipped wire and repaired it with DUCT TAPE!! We could have killed that dude. LOL

Anyway, the TDR gave us the distance to the short. We have 500 - 600 of wire and no way other than digging or replace with new wire. Anyway, the management company and landscaper know how difficult this is, so when the developer starts to talk about $$$$ they jump on his desk for us.

It gives us a confidence so to speak, some of the repairs we can make I know only a very select few in our area can do.

I do not want to sound arrogant when I say this, it just goes to show we do not have many REAL irrigation service companies in my area:laugh:

1idejim
05-27-2012, 11:48 AM
It gives us a confidence so to speak, some of the repairs we can make I know only a very select few in our area can do. I do not want to sound arrogant when I say this, it just goes to show we do not have many REAL irrigation service companies in my area:laugh:

makes a BIG difference.

Irrigation Contractor
06-02-2012, 10:17 AM
If you're going to be doing any electrical measuring, get a Fluke, they'll last forever.

http://www.flukemeters.com

Which Fluke unit are you using? The 773 and 772 have a small clamp or jaw so I was wondering how they worked or do you use a different model?

1idejim
06-02-2012, 10:25 AM
Which Fluke unit are you using? The 773 and 772 have a small clamp or jaw so I was wondering how they worked or do you use a different model?

i was using the 87trms until i blew its brain out. bad bad jim
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Irrigation Contractor
06-02-2012, 10:31 AM
i was using the 87trms until i blew its brain out. bad bad jim
Posted via Mobile Device

I have been looking at getting a few of the new Milwaukee Clamp Meters since I can get a good price on them, but none of them specifically state "milliamps" in the description.

What exactly am I looking for to make sure I get the right units? I do not mean to disappoint you Jim!! I just have bad luck ordering the wrong parts all the time:hammerhead:

Wet_Boots
06-02-2012, 03:57 PM
I have been looking at getting a few of the new Milwaukee Clamp Meters since I can get a good price on them, but none of them specifically state "milliamps" in the description.

What exactly am I looking for to make sure I get the right units? I do not mean to disappoint you Jim!! I just have bad luck ordering the wrong parts all the time:hammerhead:"leakage meter" is one descriptor of the right item

1idejim
06-02-2012, 04:46 PM
4 digit 0.000 display true RMS leakage current tester. just copied from my p93 manual
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avernon0112
06-05-2012, 08:51 PM
I got the armada clamp meter in yesterday! I went with the armada just on price point. I go out today and put it to use and find a fault. Wire path comes out of a splice box and tees of in two directions. The next two decoders have nothing coming to them. I pull out my brand new Armada GFL hook everything up and the needle on the A frame moves no where? So I try hooking it up on the other end of the valve and still the needle moves no where? I read the directions two times and triple check everything and cant seem to find anything.Has Anyone had this happen before?

Sprinkus
06-05-2012, 09:10 PM
If there's no current past the tee splice then check those splices. A bad connection inside of a correctly sealed splice will usually not show up as a ground fault.

avernon0112
06-05-2012, 09:22 PM
If there's no current past the tee splice then check those splices. A bad connection inside of a correctly sealed splice will usually not show up as a ground fault.

I was thinking that. The wire comes from one splice box out and under a road then tees to the valves. I traced the wire across the road and then traced the wire running between the valves and figured that would be where the splice was. I probed and probed and probes some more. Still didn't't find it. I think this would be a good job for the TDR. It would have bee good to have today. Spent a few hours trying to find one bad splice. It was in a 6 inch VB 6in in the ground. King wire nuts and the tiny ones at that.

Sprinkus
06-05-2012, 09:42 PM
I worked with a guy that had to troubleshoot an intermittent problem with a large scale system. Turned out that the guy who pulled the wires through the sleeves did it with a truck! He ended up skinning off the insulation on a bunch of the wires, which caused them to fault anytime the system irrigated.

1idejim
06-05-2012, 09:44 PM
The reason i perfom short to earth measurements is to tell me where to look and what tool to use. like sprinkus said, if there is no path to ground the GFL isn't gonna work. if you are concerned with the GFL run a piece of wire above ground and strip 1 end, wrap the bare wire around a screwdriver and insert the driver in the ground. connect the transmitter to the other end of the wire and earth ground. turn both units on, the frame should kick toward the screwdriver.
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avernon0112
06-05-2012, 09:56 PM
The reason i perfom short to earth measurements is to tell me where to look and what tool to use. like sprinkus said, if there is no path to ground the GFL isn't gonna work. if you are concerned with the GFL run a piece of wire above ground and strip 1 end, wrap the bare wire around a screwdriver and insert the driver in the ground. connect the transmitter to the other end of the wire and earth ground. turn both units on, the frame should kick toward the screwdriver.
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I will give that a shot tomorrow. I am would think it is good being brand new just concerned. Have you used the sstdr enough to know if you think it is any better than the TDR?

Mike Leary
06-05-2012, 10:00 PM
I am would think it is good being brand new just concerned.

Works for me.

1idejim
06-05-2012, 10:53 PM
I will give that a shot tomorrow. I am would think it is good being brand new just concerned. Have you used the sstdr enough to know if you think it is any better than the TDR?

test the GFL. I have had out of the box issues with more than a few tools, even Armadas. Knowing how to run an operational test helps tell you if the instrument is working correctly. I can say that i am very happy with the snapshot so far. It takes a lot of use for me to become at ease with a tool without having a backup to bail me out of a nightmare job but i feel confident with the sstdr. I pm'd you my number just in case.
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