you measured power and it is high. Load is too less and pump is working hard. 2.8 amps. 644 W.

It is doing more then nominal. It will heat up till thermal trip.

You could make a bypass of water, circulating back through valve to tank and regulate flow, until it is on 300 W 1,3 A. 

Also flow out of hose could be less then.

You could have bigger hose, so less pressure drop and more waterflow. Measure to 300 W, 1,3 A.

Pipes are mostly specified with pumps. If you, at the end go back to 1/2 inch, you maybe could have problem back.

Maybe not as the rest of the hose line is bigger.

There is a quadratic increase in resistance by pipes, due to speed of fluid. The more flow , the more (quadratic) resistance.

The more power you need. What I remembered from long time ago.

Maybe with a  pulse wide modulator, you change frequency. Pump will run slower, less, 300 W set.

Measuring on feed of pwm. Voltage steady 230 volt and power 1.3 A then. Of course less water at end, but probably no trip.

 

On 12/30/2023 at 5:04 PM, Crossy said:

Yeah, pumping direct from the mains is "unwise" (let's not get into the argument of whether it is actually illegal).

 

A buffer tank makes life much more bearable for your pump and prevents you from sucking in the contents of the neighbour's duck pond 

 

I have 5 rows of 4 ongs cross connected. The mains fills 4 tanks and the bigger lumps of silt sink to the bottom of the ongs. Each row of 4 then run through 2 replaceable 5 micron filters and then to the pump, which is by coincidence, a Mitsubishi EP 305 pump.

 

I still see around the toilet bowl, the shower head, and even in the 200 litre water barrel has silt smaller than 5 microns. If the OP doesn't have filters before the pump, then perhaps silt may be partly blocking the input feed, or even the pump output pipe, making the pump work harder and thus overheating.

 

My system is similar to Crossey's drawing posted by MCJM except that I have 4 tanks connected and after the tanks I have 2 x 5 micron disposable filters before the pump input (valve #1 on the drawing).

 

The Mitsu pump has 1 inch connectors and if the pipes connected to it are smaller (1/2 or 3/4 inch bore), this could also affect the water flow and make the pump work harder and overheat.

I had always thought HITACHI was better than Mitsubishi....for motors/pumps like this....

 

Anyone here agree with me?

 

 

1 hour ago, GammaGlobulin said:

I had always thought HITACHI was better than Mitsubishi....for motors/pumps like this....

 

Anyone here agree with me?

 

 

No, they are both good.