Looking for 60 meter water level measurement transmitter

P

Thread Starter

Pavan

I am looking for 60 meter water level transmitter for a Surge Tank having diameter of 10 meters of a Hydro Power Plant. The water level can have sudden rise of level (in few seconds) and with water force upwards when the plant is stopped suddenly.

I thought of two options:
1. Ultrasonic based
2. Submersible pressure transmitter

Ultrasonic will be costly option being large range. And may give slow and false readings due to direct and reflected waves from tank walls. Please suggest options, who support such high range, as mostly 25 meter range is the limit for Ultrasonic, and if it will be correct choice?

Submersible Pressure Transmitter seems to be OK, in terms of response, range and cost. But what may happen when sudden surge comes and water rises with great force upwards, will the sensor remain at its location or may flow down in the overflow exit near top level.

Thanks
Pavan
 
Pavan,

A submersible will work -- with a stilling pipe. Although a flanged pressure transmitter will also work (without going down the overflow stem) if you can place it at the minimum level to be measured with a valve and other fittings to accommodate the instrument (and future removal)---(many manufacturers can supply the instrument).

Dennis
 
> Ultrasonic will be costly option being large range. And may give slow and false readings due to direct and reflected waves from tank walls. <

Recent advances in ultrasonic signal processing algorithms have improved ability to detect surface amongst all the return echoes, but speed of response is still a factor.

Rather than ultrasonic, I'd suggest radar for non-contacting, top mount level detection for faster response.

Siemens LR460 radar is rated to 100m.

> But what may happen when sudden surge comes and water rises with great force upwards, will the sensor remain at its location or may flow down in the overflow exit near top level. <

If you anchor the submersible, it won't move.
If you don't anchor the submersible it'll flutter or move. Most installations include a stainless steel cage the surrounds the transmitter. THe cage provides a larger area against which the force of the rising water can impact.

The installations I've been involved with use the cable and venttube assembly to bear the weight of the submersible. Nothing says you can't use a stronger steel cable and put a heavier weight on the cable, if you cannot anchor it.

You do have to take steps to make sure that condensation doesn't collect in the vent tube with submersibles.

David
 
Did you find one? I have submersible with the appropriate anchor device and fast enough reaction time to handle the surges.
 
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