SURT10000XLI for medical machine

[bazzil_apc]

This was originally posted on APC forums on 1/7/2016

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Hi there! A customer of mine has a medical machine (laser) that it needs 7500 VA maximum and max current 40A . I'm between SRT10KXLI and SURT10000XLI which is older model. I found a good offer for a brand new SURT10000XLI. Does the SURT10000XLI is enough for this machine? I'm asking that because the SURT10000XLI is 8KW and SRT10kXLI is 10KW. Both are 10KVA. I will appreciate any help.

[mitsmith_apc]

This was originally posted on APC forums on 1/8/2016

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Hi Vasilis,

I first want to mention that we do not have any UPS that is medical grade. I would also advise to not use a UPS in conjunction with a laser. Especially one of this size. When turned on lasers draw a sudden high current and UPS's have a hard time dealing with this spike in current. Lasers are also known for causing power sags in power circuits (similar to how you may see your lights in your home dim when the refrigerator motor kicks on). This also does not play well with UPS. You can properly size a UPS that can handle 40 amps but have it not work with the laser due to its operating characteristics. 

With all that in mind, the device says that is has a maximum of 40amps. If we go with the SURT10000XLI that is rated at 8KW. If the unit is running at 230volts that would lead to about 35 amps capacity (8000/230). The SRT10KXLI is 10,000/203=43Amps. With lasers I would go with the larger unit. You will have a higher likely hood that it would work with a higher capacity unit. 

[bazzil_apc · Accepted solution]

This was originally posted on APC forums on 1/10/2016

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Hi Michael. Thank you for your answer. I went to my customer to get a photo of this machine. You can see the machine here. I have ask from the manufacturer to send me some technical details about this machine. The only work that we want to do the UPS is to keep the machine alive after current cut for 3 min just to shutdown normally. The clinik has 3phase current and one phase used for this machine only. From that you have wrote (my English aren't so good) i understand the SURT10000XLI is not good because it's give 35A (the machine is 220-230V) that is less that the maximum that machine wants. The SRT10KXLI gives 43A and that is good. Right? I will be back on moday with more details. Thank you for your help.