Hi,

I've had five current transducer stop sending output voltage shortly after installing them in our system. I suspect somehow our system is "burning" them out. On initial install we would see the output voltage we would expect but after one or two checks the output voltage would go to -2.9VDC and stay there even if current was present.

We are using the current transducer for measuring Welder current @ a max of 35AMPs DC.

We suspected that there might be in-rush or a spike from the welder that is taking the current sensor out. We performed a remote isolated test. We connected power to the current transformer directly to a 24VDC power supply. We clamped the current transformer to the output of a different power supply and ensured that the conductor was properly oriented (Direction or current). Using a DMM we measured 0.06 VDC with no out put from the power supply and 0.11 VDC when the power supply was enabled. We took this as a good reading and performed the test a couple time and received the exact same measurements. I have attached a schematic - it's pretty straight forward.

A couple of days later we repeated the same test using the same equipment. This time the DMM reported -2.9VD on the output from the current transformer, in all situations.

I noticed that the current transformer has a max rating of 50mA. I was going to add a fuse to the circuit. But, if this is the issue, a fuse will most likely continue to blow and have to be replaced/ reset on a regular basis.

I am wondering if there are any additional ideas on what might be causing this issue, or integration ideas.

Thank you