Hi All

We have 4 x 12KW 3P Sunsynk inverters in parallel with 10 x Pylontech UPS5000 batteries to run OTIS Regen 5 lifts(4 lifts) The system works well during loadshedding but we found that the inverters does not respond to any Power fluctuations. Seems that the drop in input power causes the lifts to fail. Any suggestions

34 minutes ago, Nu Power said:

Hi All

We have 4 x 12KW 3P Sunsynk inverters in parallel with 10 x Pylontech UPS5000 batteries to run OTIS Regen 5 lifts(4 lifts) The system works well during loadshedding but we found that the inverters does not respond to any Power fluctuations. Seems that the drop in input power causes the lifts to fail. Any suggestions

I am not sure what you mean by power fluctuations? Is this when loadshedding starts or ends or something else? Can you see this on any charts that you might have. Can you share those with us?

@HendrikBigChief,

I think @Nu Power is describing the "inrush startup current problem" of an electric motor e.g.  borehole pump starts up.

What is the rating of the lift motor? I'm presuming them to be pretty huge, compared to fridge/pool pump motors.

or what else?

Read that post of taliab, quoting below as well :

"Inductive loads have inrush(surge) currents typically 4-10X the run current. Best to measure inrush current with a meter that has the INRUSH function. Size inverter accordingly.

 

HF inverters have no meaningful surge capabilities in most cases. They don't have the large transformers present in LF units, and can't do it. Their surge ratings are often for an AC cycle or two (1/50th of a second).

 

If you don't want to live with regret, you size an HF inverter to accommodate the entire inrush surge within it's continuous rating."

 

 

The Sunsynks may not be ideal for lifts due to this. 

But get the exact specs of the lift from the manufacturer, or test the draw yourself. 

Edited September 2, 20241 yr by abd7

1 hour ago, abd7 said:

ir surge ratings are often for an AC cycle or two (1/50th of a second).

The Sunsynks won't be ideal for lifts due to this. 

Are you saying the 5sec 2x rated power on one common inverter and 10sec 2x for a Deye/Sunsynk as per specs is a false claim? 

9 hours ago, Nu Power said:

Hi All

We have 4 x 12KW 3P Sunsynk inverters in parallel with 10 x Pylontech UPS5000 batteries to run OTIS Regen 5 lifts(4 lifts) The system works well during loadshedding but we found that the inverters does not respond to any Power fluctuations. Seems that the drop in input power causes the lifts to fail. Any suggestions

I assume that the 4 x 12kw 3p inverters power all 4 Otis lifts? What is the 3ph input breaker sized that powers the lift from utility. Are the lifts using Gen2 drives with gearless PMSM(Permanent Magnet Synchronous Motor) or non generative drive with induction motor?