Interpreting Data Logger Info

[JDFreeman88]

2500 Amp 480 Volt Service feeding 4 busways, 3 @ 800a 1 @ 1000a in a manufacturing facility. I was given some data log graphs showing the current load over a 24 hour period. To keep things simple, the 2500a shows an average of 2000a with a few ~2600a spikes. The 1000a bussway has numerous spikes around 1200a and highs of near 1600a ... What I would like someone to explain, is what those spikes mean ... is the system overloaded ? .. is this normal of a facility with 100+ large motors running 24/7 ... I'm really looking for a good explanation on how to interpret this data....

 

[gar]

160928-2419 EDT

What is the time resolution of the data logger? For example 1, 5, 20. 60 seconds, or even longer 5, or 15 minutes. Short duration spikes of less than 1 second of the magnitude you mentioned, and not occuring too rapidly are not a problem. What is really important for low level overloads is the temperature rise in conductors and other components.

If the averaging time of the logger is long, and these spikes occur rapidly, then your values might be a problem.

Ultimately temperature rise is the important criteria.

If you had very high current peaks (like dead shorts or charging capacitors), then you might have mechanical problems from the magnetic forces generated.

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[Meterman Eng]

Datalogger and Type of Data?

Datalogger and Type of Data?

I may be able to help interpret the data, as I have experience in the high-end metering market (mainly upstream of the service point).

What is the type of datalogger used and what is the type of data that was logged (i.e. instantaneous, half-cycle RMS, 10 sec RMS, does it include harmonics or is it fundamental, etc...)? The more details you have, the better I should be able to help.
...Not sure if you can send me the data, but it would help me. Digital meters and dataloggers process (digital signal processing) the metered quantity at least in some way. Interpretation hugely depends on how the quantity was internally processed. It is most likely RMS type data, but the RMS value will (may) be different if taken (aggregated) over different time intervals.

For example, if the RMS current was calculated then logged over only one cycle during which time a motor was starting, it would report near the starting current of the motor. If the RMS current was aggregated then logged from the whole day, it would more closely report the normal operating current.