Pump motor power sensing

[JohnW]

I have a requirement to sense the true power used by a submersible pump so that I can monitor pump performance. Anyone using anything that can do that and give me an output to a PLC, either analog or Profibus DP.

 

[rdrast]

I've had excellent results with True-Power monitors from http://www.loadcontrols.com/products/products.html

 

[chief weegum]

It is a soft start control, or simple contactor or a VFD?

If is a vfd, you can use a drive connected on a devicenet network. You will be able to monitoring the current or something else you're interresting.

Overload could be monitoring in a devicenet network.


Forget it if it's not on a plc setup.

 

[Ken Roach]

Do you need to monitor "true power" or is ordinary 3-phase current monitoring enough ?

The first thing that comes to mind is the Siemens Simocode overload protection relay, which will let you read the power being drawn by the pump over Profibus DP.

Most makers of soft-starts also have a communication option that includes Profibus.

The link rdrast provided shows a very good dedicated-purpose load monitor that measures true power.

 

[Jim Dungar]

I have had good luck with products from NK Technologies. They have a nice small unit (model APS) for use on balanced three phase loads.

 

[TConnolly]

I've also used the units from load controls that rdrast recommended. They work very well. 0-10V or 4-40mA outputs with setpoint relays and true power - I think they even have some special models for pumps.

 

[AutomaticLeigh]

Try Charter Controls http://www.charter-controls.com/
I have used one of the Unipower units, but I can't remember which. I think Rayleigh also have a number of units for power and angle.

 

[JohnW]

Thanks guysI shall have a look at those, I am probably going to use the Simocode for new installations but I think that the Loadcontrols Universal is the bit of kit for upgrading existing starters.

Ken, yes it is true power, current and apparent power is not linear. I found this at LoadControls that exlains it. http://www.loadcontrols.com/application_notes/pdfs/power_sensors&_load_control.pdf

 

[MarkTTU]

I've used the Emotron and found it to be easy to setup and very good.
http://www.emotron.com/templates/Page.aspx?id=169

Output is 4-20mA; I set it to look at % HP in use, but it can be set to a lot of different readings (KW, %KW, HP, etc).

 

[DriveSuperFreak]

True Power Measurement

I have a requirement to sense the true power used by a submersible pump so that I can monitor pump performance. Anyone using anything that can do that and give me an output to a PLC, either analog or Profibus DP.

Try to use energy meter. There's a lot of meter offering this with a provision of transmitting data's over rs485.

 

[danw]

I've used the LoadControls unit which you posted with great success. It was sensitive enough to get relative viscosity measurements through motor power. Good unit.

Dan