Testing for wire break in White's TDI Search Coil assembly

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How do I go about testing to make sure that the White's TDI Standard 12 inch Search Coil and Cable assembly does not have a wire break in it?

 

[GoGoGopher]

Need to know the pins for the pairs of wires, then just do a continuity check on them...If no indication, the wire is open somewhere...I have no idea what the pinouts on the coils are though

HH,

 

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I did not know the TDI had pairs. So, I decided to take a look and the GoGoGopher is right. Pins 1 and 2 are paired. The other pair is 4 and 5. Pins 1 and 5 look to be the ground pins.

I tested for continuity. Pins 5 and 4 show continuity. Pin 5 also shows continuity with 2. Pin 1 shows no continuity at all. Doesn't look good for the moment. Shouldn't pin 1 show continuity with pin 2?

 

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In another forum a question was asked:
...which pins on the Whites round coil are for transmit- receive & shield?

Answer:
pin 1 = RX-
pin 2 = RX+
pin 3 = Shield
pin 4 = TX+
pin 5 = TX-

As I suspected pins 1 and 5 are ground.

The forum continues to ask ...I would like to do a continuity test to determine if any breaks or damage exists in the search coil assembly. My understanding is that it is a dual field coil;therefore:

Should pin 1 only show continuity to pin 2? Answer = yes with exception of possibly including pin 3.
Should pin 4 only show continuity to pin 5? Answer = yes with exception of possibly including pin 3.

It appears depending on which design coil is being used the wiring can get interesting as such that the RX or TX coil (but not both) will share the shield pin 3 on checking continuity.

Forum = http://www.geotech1.com/forums/showthread.php?t=15729

My continuity check shows that the TX pins 4 and 5 are making continuity with RX pin 2. I am going to have to locate another standard coil for the TDI to determine what is to be considered correct readings. Providing the coil being compared to is correct to begin with.

If someone else has a TDI and can do a continuity check on the standard search coil that would prove to be a valuable test. Also, I think someone with an aftermarket search coil should do a test to see if there is any agreement on continuity.

 

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Well, I spoke with Jimmy Sierra about the continuity check and he said he wasn't a tech and could not say if the test was correct. Instead, he just shipped one out to replace what appears to be a good coil. I didn't want a replacement...all anyone had to say was that it was good to go. That would have made me happy. FYI: The replacement coil has the same pins showing continuity.

 

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Just a hop, skip and a jump and there you are...walking about with what might be the wrong search coil or not!

Wiring for TDI looks confusing compared to MineLabs.

Have a look here: http://www.geotech1.com/forums/showthread.php?t=15792

After that look pins 2 and 4 will always be testing for continuity and only pins 4 and 5 can be tested. So, it looks as though there's no break. Wonderful!