Rosemount Radar Level Transmitter 5402 no signal

We have a 5402 LT without its cone antenna installed and it was working perfectly.

But later, after few years, it started giving a BAD signal.

It is mounted on a flange with 2 inches pipe under.

We did not installed the 2-inch cone antenna because it doesn't fit into the 40mm hole of the flange.

The pipe length under the flange is 530mm.

The tank height is 1500mm.

Total height of the LT from the "0" ref (bottom level of tank) is 1500mm + 530mm = 2030mm.

My questions are:

1. Is it because the cone antenna is not installed that's why it is giving a BAD signals now?

2. Can we retrofit the LT with a rod antenna? If yes, what are the things need to consider to retrofit the rod?

Thanks for your responses.

  • In reply to Rein:

    Hello Rein,
    The echo curve is our best tool to show the actual health of the unit. In this case, the total absence echoes clearly indicate that not only the reference pulse is missing or is diminished, it is also a clear indication that there is no energy sent out. I cannot imagine that any erratic setting of any of the user configurable registers can cause this behaviour. I thus strongly believe that this unit is broken.
    Best regards