# How can I measure the amount of energy consumed by the robot in KWh?

Birmingham
- I am using Analyzer on RobotStudio, to monitor the energy used, but at the end of the acquisition, I have only max and min value in Watt. Can I calculate the Total amount of energy used?
- On the graph I had positive and negative values. The negative ones are related to energy recovered?
Thanks

• Sweden ✭✭✭
From the RobotStudio operating Manual (check the part in italics)

Total Motor Power
The Total Motor Power signal shows the total instantaneous power for each joint. It may be positive or negative.

The instantaneous power for a specific joint is positive when it accelerates and negative when it decelerates. If one joint is accelerating at the same time as another joint is decelerating, then the negative energy from the decelerating joint is reused by the accelerating joint. If the sum of the instantaneous power of all joints is negative then the power surplus cannot be reused but it is burned off in the bleeder.

For a virtual robot the signal is based on a nominal robot during typical conditions, for a real robot the signal is based on the torque for that particular robot in the actual conditions. For a real robot the value of the motor power signal depends on various factors, for example, the temperature of the robot and the length of the cables.

Note: Total Motor Power signal represents the power consumed by the mechanical robot arm and not the power that is fed into the controller cabinet from the power network. The power used by the controller cabinet is excluded.

Total Motor Energy
The Total Motor Energy signal is the cumulative sum of the positive part of the Total Motor Power.

Purpose of signals
The purpose of the Total Motor Power and Total Motor Energy signals is to provide an estimate of the power and energy used by the robots. For virtual robots, these signals can be used to identify peaks in the power usage to enable the robot programmer to adjust the robot program with the aim to reduce the power consumption. For real robots, the signals can be used to compare the power usage of different robot individuals running the same robot program, to see if any robot differs significantly from the others. Any such deviation may indicate that the robot needs maintenance.

Henrik Berlin
ABB
• Shanghai
Dear Henrik Berlin,
We get the power consumption via PC SDK API,but we don't know the unit of the figure ,W？KWh？J？,Would you please tell us?
And for the negative power consumption , should it be changed to absolute value and accumulate to the total motor power consumption?