Cable testing

[jimmykk]

Hi I have a cable consisting of coax wires. On one end of this cable:The outer conductor of these wires are connected to common ground while inner conductors are soldered on SMD pads for signal flow. This end is unfortunately not accessible as it is enclosed in a housing. Similarly, The other end of cable is connected to a connector to their respective pins. This end can be measured.
so my question is there any test I can run to check if there is continuous connection of the cable. That is Wires are soldered on SMD pads and on the other end, they are connected to the pins.

 

[KlausST]

Hi,

I guess the SMD pad is not the end. Are there any traces and/or parts connected?

Klaus

 

[jimmykk]

Unfortunately, nothing is available as measurement point on the SMD pads end. This end is completely sealed. I was thinking of more like a capacitiance measurement between ground(outer conductor) and signal(inner conductor).

 

[KlausST]

Hi,

No need to be "available". I just asked what's connected.

Klaus

 

[jimmykk]

A sensor element is connected and we can’t run that yet.

 

[stenzer]

Hi,

A sensor element is connected and we can’t run that yet.

as you are using a coaxial cable, it sounds to me your sensor is providing an analog output. So, if you power up your device I assume you should be able to measure a plausible value (voltage).

Why aren't you able to operate the sensor at the "moment"? Or do you mean it does not work as intended?

BR

 

[KlausST]

A sensor element is connected and we can’t run that yet.

You couldn't be more vague.
Or is it a secret

Klaus

 

[jimmykk]

Thing is we do not have any equipment to test it other than multimeter/LCR Meter.
The only thing that is accessible to us is the cable end with loose wires/connector.

 

[stenzer]

Are you able to turn your sensor on?

 

[dick_freebird]

Time domain reflectometry. Pop a single pulse down the line
and look for the reflection on an oscilloscope. Characteristic
length, or something else, going by time of flight? If you are
good you can "see" connectors and other minor discontinuities
in the waveform (though it helps to know what and where
you're looking for).

 

[KlausST]

Time domain reflectometry

Hi,

I agree this could be possible..
But without any information about the sensor .....we can't be sure whether the pulse hurts/kills the sensor.
It's like drinking from a bottlle with unkonwn content. It may be water, wine, poison, chemicals, hot, medicine, fuel...

* I can't give a recommendation to test the cable when an unknown sensor with unkonown behaviour is connected to the cable.
* Either disconnect the sensor and test the cable alone..
* Or get information about the sensor

Klaus