Scale sensor with permanent/static load

Hi guys, I would like to ask you if you know about some sensors for arduino for scale for permament load.
You can imagine it as kitchen scale, but on the start there is already some heavy stuff on (cup of water)
So the scale can be for example turn off (to save an energy), but cup of water will be still there and when it wake up, I wanna to know if again value how heavy it is.

Most of sensors are not for permanent load and I am not sure if that sensors can handle this situations (when there will be something on for example for 2 months). But if you have some experiences or know about some sensor which is good for that. I will be very glad.

Thank you.

This is the situation with any scale which has the weight of the pan etc on it .
You measure the weight and just set that as a fixed value. ( or your zero) , if anything is added you weigh it and subtract the previous value .
You can store that initial fixed value in Eeprom.

Also google “ tare”

Hi, I get your point, but probably I didnt explain it well.
I am looking for sensor which can be under some weight all the time.
Example: Beehive.

You have sensors under this beehives but you dont wanna to have the arduino all the time ON.
So you will turn it off. After hour, you will turn it on and you have still that beehives on that scale sensors (but even more heavy than last time).

So my point is even i will have value how heavy it is before I turn it Off. Next time when I will turn it ON it can be one kg more, so even tare will not help me in this case.

So my question is, is there any sensor which can be "nonstop" under pressure even I will turn it off and it will be ok to wake up him and I can say him "last time you measure 15kg, how much it is now?" and he will say me "now its 17kg".

The sensor is not the issue.

The program that you write for the microcontroller can store the weight on the scale when the power is turned off, and use that stored information when powered up again. Arduino microcontrollers have EEPROM for just such purposes.

As pointed out in reply #1, most scales already do some form of this. The pan is not part of the sensor.

A standard load-cell will have a little creep over time, but may be OK if you de-rate it somewhat, and
there are ways to estimate and correct for creep if you monitor temperature. There are probably specialized
low-creep load-cells available too.

The alternative is to have a means of loading and de-loading the cell so the measurement can be differential,
perhaps a short-range actuator to just lift the platform off the load cell. By monitoring the reading you can
tell when the load-cell is no longer taking any force and when its taking all the force. You typically only need
a few mm of movement to do this.