Instantaneous, Average or Maximum, which on do I use it for additional load of MDB.

[Traiwit J.]

In order to install new machine, so we used the power analyzer to record the capacity of MDB.
The question is which one is to use for considering the capacity left for MDB.

Thank in advance.
Traiwit J.
Bangkok, Thailand.

 

[topgone]

I recommend using the maximum load for deciding the capacity or lack thereof. The maximum demand should not be greater than the rating of the panel.

 

[don_resqcapt19]

Typically you use the 15 minute maximum demand of the existing loads to determine the ability to add new loads. If possible you use the maximum demand over the previous 12 months. In the US, the information is often available from the utility company.

 

[Traiwit J.]

Thank you for your comments.
Do you have any reasons for using Maximum?
I wish I could show you the recorded data, any suggestions?
Thank you all again.
Traiwit J.
Bangkok, Thailand

 

[Traiwit J.]

Here are the recorded files.
If there is any comments. please suggest me.
Thank you.
Traiwit J.
Bangkok, Thailand

 

[winnie]

The rational for using _maximum_ measured load when adding new load is that the new loading would presumably increase this maximum loading.

If this maximum load exceeds the rating of the feeder/MDP/transformer/etc, then you have overloaded the component.

On the other side of the coin, equipment is _expected_ to be overloaded for short periods of time; this is why circuit breakers have time/current curves. When demand data is used to evaluate available capacity, it is always averaged over some 'reasonable' time period. Thus as Don notes it is typical to use the maximum 15 _minute_ demand for purpose of determining the existing 'maximum' load.

I would note that your maximum current report appears to be based on a 15 _second_ measurement interval. The 15 _minute_ maximum demand will be between your 15 second and 1 hour data.

-Jon

 

[kwired]

can depend characteristics of current load and added load.

say your maxim load contained a lot of Process A but process D that you are going to add would never run simultaneously with process A then you only need capacity for whichever is larger.

Heating vs cooling loads can be this way as well.

 

[Traiwit J.]

Thank you all for your comments and suggestions. I forgot to tell you that 80% of MDB's existing loads are compressor loads (Motor Drive), and new load is the same type.
Traiwit J.
Bangkok, Thailand.